This topic has come up a few times in the past, and a quick search may reveal some more information for you.
I like my upconverting DVD player, but one thing that you need to know is that it does not, and will not, no matter what brand/model you buy, turn your regular DVDs into HD-DVD or Blu-Ray quality. Upconverting is basically taking your 480 lines of video and, using mathamatical algorythms, it does a "best guess" average and "inserts" more lines of resolution based off of these mathamatical calculations to make an artificial "higher definition" output.
Make sense?
Anyway, I know that Sirquack went from an upconverting DVD player, to a Home Theater PC, and he can tell you (as would just about anyone with a HTPC) that it is even better at matching the resolution to your display device.
Now, some displays will do the upconvertion for you, some are better than others.
Good luck.
