Weird External HD problem

So…This is strange:

I am trying to repair a Hard Disk. It was corrupted at some point. Here’s a list of things I’ve tried.

Inside the original case:

Ran Chkdsk:
Made it to 50 percent after which it said it cannot continue.

Ran ERD Commander and ran DiskCommander. No Dice, nothing.

Connected it externally to a MacBook running XP. Could see the disk, but no other information.

Now…here’s the weird part.

I connected it to my MacBook, running Leopard, and I see the files fine and I can easily read them

But when I try to plug it in now, I get a blue screen error.
When I try to use ERD commander I get a bluescreen stop error
Any idea what is going on here?