DLP tvs are great. Mitsubishi is the only player left in that game right now, unfortunately. It's still the most reasonable way to get a large picture without going to a projector and screen setup.
All of those tvs will dwarf your current samsung - with the smallest of the four I linked, you'll have 170% of the samsung's viewing area. Picture quality should be just as good if not better, imo. The price is fantastic when you compare it to the costs of large lcds or plasmas.