For under $100, an HD-DVD player is the way to go. The XA2 is the best, but any HD-DVD player out there does a great job, and they're dirt cheap. If you want to spend a few hundred, there's a Samsung Blu-Ray player that also has the same chip as the XA2, so it would be a good choice.
If you just want the very best and money is absolutely no object, AND you don't care at all about high def formats, there are some other options. Denon makes an amazing player. But I just can't see spending hundreds on a DVD player these days, particularly if the point is to get the best video you can.