In the situation you’ve described, the three most significant factors are:
- the highest SCREEN resolution of the monitor.
- the tuner/capture hardware/CPU you are using
- the TV software/drivers you are using.
I have used computers and presentation projectors to make 10-12 foot diagonal front projection TVs for myself and friends. Personally, I find NTSC on 640x480 to be a bit disappointing, even though that is close to the resolution limit for NTSC. I find anything at 640x480 disappointing. However, I’ve had friends who were thrilled with it. At 1024x768 or higher, the apparent NTSC picture quality depends on the hardware/software/driver’s ability to interpolate to the higher resolution.
I’ve had decent NTSC viewing with a 466 Celeron with the right OS/software/card, but it was a bit weak for recording (probably due to bus transfers). A slightly newer mobo, with better IDE, and an 800 MHz PII (which has a 100MHz CPU bus, vs. the Celeron’s 66MHz) handled viewing and recording like a champ, but I’ve seen 2GHz+ systems fall a bit short where the 800MHz soared. Go figure.
Some cards never handle full screen display very well. Sometimes the software or drivers that ship with the cards stink, but the card works well with free alternatives like TPMGEnc, VirtualDub, reference or ‘tweaked’ BT8x8 chip drivers (The BT848 and BT878 are the most common chips used in TV tuner/capture cards). You can find the above with a Google search. You’ll also want a serial port remote control and freeware/cheap configurable remote control software.
There are varuious sources for info on these. Perhaps the best is AVSforum - but they can be very technical (though they have a lot of nuts and bolts summaries and FAQs, they can require a little digging to find) Find an information source that suits you. It’s fascinating.
You can pre- test (for your tastes) this by hooking up the largest normal monitor you have available, and examine the picture closely. Be picky because larger screens tend to magnify flaws. Don’t give up if the results are disappointing, until you’ve played with the above software and drivers (which are just a few of the more common and better-rated options in the “computer video on the cheap” category
Overall, yes, it could be the best $100 TV you ever got. You may begin to notice defects after a while, but visitors may still be impressed. In a couple of years, you can upgrade to an ATSC tuner card (I’ve seen the MyHD card, which could work well in your case, as cheap as $250 new. It’s price will undoubtedly drop in a year) With an HDTv card, a cheap HTPC (Home Theater PC) can do things with HDTV (like recording, program guide, and fancy Dolby sound) that would take thousands of dollar in consumer gear.
I can’t promise you optimal results, because there are so many personal and system factors. However, I’ve often had great results.