I have what I think is a very similar TV (same model #, but with an A at the end) and it is in the running to go into a Smash TV cab for my homebrew game project. Mine is actually 26" in reality, has component, and does return to power/input when you disconnect and reconnect power. I have actually been looking for a spare locally- but I am not sure that my "A" model is the same as your DTV2798.
(My debate on it is whether I want to design my game in 4:3 so it looks like an old school game or just do a 16:9 LCD and not make a heavy cab way heavier... I am still waffling on this).
Anyway, just my 2 cents, looks like I might have a similar model to that one. Of course, at last count I have 14 project TVs... I have a problem....