Try this:
Open My Network Places. If you don’t see the shared folder on the other 'puter right there under Local Network, then click “View workgroup computers” on the left. Do you see the other computer now? Good. 
Click it. There should now be a list of shared folder on that computer. After you use it once, it should automagically begin showing up at the top of My Network Places.
Also, when you say can only ping in one direction, are you pinging the machine name or the IP? If you haven’t done so, try “ping 192.168.1.1” (or .2) and see if that works both directions.
Phew! Okay.
I’m pinging the IP address.
I don’t see New computer anywhere in the Network Connections things when on the Old computer.
I don’t see Old computer anywhere in the Network Connections things when on the New computer, I just see my own shared folders (created from that horrid PDF thingy I guess, since they appeared then).
Old’s ipconfig:
Ethernet adapter Local Area Connection 11:
Connection-specific DNS Suffix:
IP Address: 192.168.1.1
Subnet Mask: 255.255.255.0
Default Gateway:
PPP adapter Dial-up Connection:
Connection-specific DNS Suffix:
IP Address: 67.31.137.181
Subnet Mask: 255.255.255.255
Default Gateway: 67.31.137.181
New’s ipconfig:
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix:
IP Address: 192.168.1.2
Subnet Mask: 255.255.255.0
Default Gateway:
Hmmm strange that you can only ping one direction. Have you rebooted both machines since changing the settings? Do it now if not.
Just to be clear, My Network Places is different from Network Connections. You can get there from the sidebar of My Computer. On the sidebar of My Network Places, there should be a network task that says “View Workgroup Computes”. What happens when you click that, from either machine?
I’ve rebooted, yup.
Actually now that I look hard, in the old computer, I only have 3 Network Tasks in My Network Places: Add a network place, View network connections, Set up a home or office network.
The new computer has View workgroup computers, with itself and the other computer in it (“Base (Base)” and “Zig (Zig)”).
If I try to double-click Base, I get a popup:
Mshome [my network group or whatever I set in the My Computer Properties Computer Name Change screen]
\Base is not accessible. You might not have permission to use htis network resource. Contact the administrator of this server to find out if you have access permissions. The network path was not found.
Old Computer = base = 192.168.1.1, right?
From zig you can see base in View Network Computers. But when you click it you get a permissions error. It sounds like there are no shared folders on base.
On base, in My Computer, is there a folder named Shared Docuents with a hand holding it? (use view tiles) If not, pick a folder somewhere in your C drive that you want to make available to zig, right click it, and select Sharing and Security. Check Share this Folder on the Network. Click OK. Go back to zig and refresh View Workgroup Computers and try clicking base again. You should actually verify there are shared folders on both computers.
Another thing to try:
On base, under My Network Places, select Add a Nework Place. Click Next. Select Choose Another Network Location and click Next. Click Browse. Do you see “Entire Network” with a plus sign next to it? Click the plus sign. Do you see “Microsoft Windows Network” with a plus sign? Expand that too. See Mshome? Expand that. Do you see the other computer? Expand it and select the shared folder. Click Ok, next, pick a name and finish (with open place automatically checked). Any luck?
We’re getting close 
Can your old PC still ping your new one? If that’s the case then you should be able to connect to the new PC by doing a network connection from the Run command.
On your new PC setup a shared folder. Then on your old PC open the Run command, and enter in \192.168.1.2. The resulting Explorer window should show you the shared assets on the new PC. You should then be able to access the new PCs shared folder and push your data onto it from the Old PC.
From past experience in connecting PCs at tradeshows and such, as long as one PC can see the other that’s all I ever needed to transfer files. It’s just a matter of whether your pushing the data or pulling it.
Old = Base = x.1
New = Zig = x.2
They both have shared folders, definitely. One is on my desktop so I can see that it’s being shared for sure.
Base: Cannot ping Zig anymore (ARGH I didn’t change anything), but cannot see Zig.
Zig: Cannot ping Base, used to see Base with the Network Places, now does not (ARGH I just restarted).
On Zig there was the Mshome thing with Base and Zig. Both were in the Network Places thing. Now it’s just Zig.
On Base there is the Mshome thing, but it has nothing ‘inside’ it - when I choose it, I wait and wait and wait, and then there is nothing to choose, the + goes away, etc.
Pinging on either results in Request timed out. Blargh. One step forward, two back.
So if you go the the Control Panel, open up the System applet and look in the Computer Name tab, do both PCs belong to the same workgroup? If not, then you need click on the Change button and add each to a common workgroup.
Wow. I don’t know what to tell you. I would try running the Set Up a Home or Small Office Network wizard on both machines. It will probably build all those bridges again but there’s a chance it’ll work.
There’s a chance it could be a dodgy cable.
Hopefully others will be along with more suggestions.
This is a situation where having a router (networking…not wood working :p)definately comes in handy.
Yeah, they’re in the same workgroup.
Any recommendations on a cheap but working router? (It’d probably only be used once, so I don’t want to spend too much 
)
Meanwhile I’m trying to get ahold of an old friend who may be able to help, and I’m going to re-do everything again. Eventually I’ll make it work or my arms will fall out from replugging in the monitor/mouse/keyboard every couple of minutes into the opposite computer. If I get one computer to see the other again (last time, I couldn’t access it even to shove my files through), I’ll try swapping the cable ends to see if it might be a cable problem.
Rawr. I hate you Old Computer. I know it’s your fault. Even if it’s the cable’s fault it’s your fault.
oh oh OH
Okay, they sort of see one another again.
Base/Old pings New (IP address): immediate response
Base/Old STILL cannot see anything in the Mshome group in the Add New My Network Place.
Base/Old STILL has no View Workgroup Computers listing in Network Tasks. (Gotta add it somehow?)
Base/Old does not have a My Network Place in Windows Explorer.
Base/Old has a shared folder.
Base/Old Run: \192.168.1.2\Docs (or without Docs) results in very long pause, then The network path was not found.
Zig/New pings Old (IP address): Request timed out.
Zig/New sees Base in the Mshome group in the Add New My Network Place.
Zig/New sees Base in the View Workgroup Computers listing in Network Tasks.
Zig/New sees Base in the My Network Place in Windows Explorer.
Zig/New has a shared folder.
Zig/New Run: \192.168.1.1 results in a very long pause, then The network path was not found.
Well, that’s sort of there but doesn’t seem to be enough to swap my files. I’m kind of afraid to swap the cable ends in case it stops doing what it’s doing now if now is enough to swap the files.
Doesn’t seem to be a firewall problem; ZoneAlarm free isn’t noticing anything, and turning it off results in the same, and XP Firewall isn’t enabled on either computer.
OK. I don’t know why I (or anyone else) hasn’t suggested this before. Just take the hard drive out of your old PC, change the jumper to eeither Slave or CS, then install it in your new PC. You can then either transfer your data and remove it, or leave it and use it as secondary drive in your new PC.
What Whiskey-Hotel (love the nick, by the way) describes will work, but if toaster goes that route, we’ll never discover the source of our angst.
Toaster, if you go that route, we can help you. But please at least swap the cable ends first. Nothing ventured nothing gained. If functionality swaps with the cable we know it’s a bad cable.
Apparently it WAS ZoneAlarm. Last night under the same conditions though, I disabled ZoneAlarm, and couldn’t get through, now I could…which I guess is a relief, considering what might have been the problem. I don’t know why the discrepancies, but whatever. Both ZoneAlarm and my old computer have been so persnickity in the past. It works now and that’s good enough for me.
Thank you guys immensely though. Your help has been invaluable, all of it. I’ve never done anything like this before, and considering the alternatives this was a very nice and fast solution. Especially compared to that devil PDF. And since I have to use this method at least once more this week, I’m incredibly grateful. Hopefully I won’t have any more problems.
And in any case, I’m very embarrassed, I promise. Be glad I hadn’t come here earlier when the main problem was “cable not plugged all the way into the hole,” or “that’s the wrong cable buy another”.
Do I need to un-fix my IPs, or are they allowed to stay 192.168.1.1? And I would still like to know why there’s no My Workgroup Computers, but not too awful much. It just seems like a kooky glitch.
Glad you have it working. I fully inderstand Eleusis’ desire to seek closure of this problem, but I wanted to make sure you knew that there was an alternative method to attain your actual goal (transferring your data) :).
As for your IP addresses, it doesn’t matter since you don’t appear to be using your ethernet connection. However, if you did ever move onto a broadband connection and add your old computer to your home network (using a router) then you would likely have to change the 192.168.1.1 address since that’s typically reserved for the router itself.