You won't be able to fix the blurry picture for viewing TV because your video card doesn't support hardware deinterlacing, therefore you are limited to software 'BOB' deinterlacing.
You are correct, Nvidia 6xxx and upwards support hardware deinterlacing (part of the Purevideo feature set)
BTW, you don't need the Purevideo decoder to get the Nvidia hardware deinterlacing working. Any MPEG2 video decoder that supports hardware acceleration (DXVA) will work.
Note however that many GBPVR users are reporting problems and incompatability issues with using the Nvidia Purevideo capability (myself included with a 6600GT). It is a bit hit'n'miss if it will work ok for you. I hope Nvidia get this problem resolved soon!
Your safest bet is to use an ATI card. ATI support hardware deinterlacing on 9550 and upwards.
Thanks for all your help Csy. I've had bad experience with ATI cards (even tho my main PC is running one), so would really like to avoid them. NewEgg has a 6200 Nvidia card for $25 after rebate, I think I'm gonna give this one a shot. Definately can't beat the price.
I build systems for a living, so I have lots of motherboards and parts stocked on shelves.
My first attempt to build a PVR with two tuners (a PVR350 and PVR150) resulted in playback so choppy I couldnt view it. I was running a barton 2600+ with a VIA chipset.
I swapped the motherboard with one running an nVidia chipset, with the same cpu, hdd, and ram as before, and all issues went away.