I should say that the software included with all of these cards is pretty spartan. If you want good PVR software then look at BeyondTV or SageTV, which you will have to pay for but are well worth the money. My preference in remotes is the Firefly remote or the Remote Wonder II.
As to how much you can fit on a DVD? Well, I would say you can get 2hrs of very good video, 3hrs of good video, and 4hrs of so-so video. That is on a standard single layer DVD, for dual layer DVD's double those numbers. You will also need DVD Authoring software, I recomend Ulead's DVD MovieFactory 4.0 (30 day free trail available for download).
I should also mention that you could do all this with a stand-alone DVR with a built in DVD-recorder and the process would be simpler, although you would lose a bit of the versatility of editing on a PC. Most users however, I think would be better off with the stand-alone setup. Maybe if you need to save space though, the PC setup would be the way to go.