Not for video quality. You will get more advanced features with a Blu-Ray disc/player than with DVD though. You could consider buying one a pre-investment in HD.
An upconverting DVD player reverts to a standard SD player when connected to an SD television set.
You cannot get a better quality on your TV than it was made to display, if that is what you are trying to do.
Blu-ray players play movies in HD. If you don't have an HD tv, it will just look normal. I don't see the point being as the Blu-ray DVD's are more expensive.