your lcd tv/monitor will probably have a resolution of aroud 1920x1080 (1080p), so any good mid-range card should be able to handle it. look for a geforce 7600 or higher or a radeon x1600 or higher. (you didn't mention gaming so i'll assume it's not high on your feature list.)
go for a gig of ram and at least 200gb... a second hard drive just for your video/media would be ideal.
as for the cpu, get a dual-core. avoid the petium-d 800 series. if you've can wait 6 weeks or so, you'll have a better bunch of cpus to choose from. amd just released their new cpu lineup and intel will release theirs in a few weeks.
I'm looking for a PC for creative work (audio, video, photo editing) and one that can handle a 30-50" LCD TV monitor. I'd like to get a 64-bit processor as I will eventually be upgrading it to Windows Vista. Any recommendations for models, video cards, processors, etc?
Any advice is much appreciated.