yeah, there isnt a real way to change the software on the tv. the reason it is clunky in the first place is the lack of any real processing power in the tv. anything that could be considered nice and tolerable just cant be found on todays tvs without a powerful chip in them. i would recommend connecting the computer to the tv as another screen with a long cord, or buying/building a home theater pc (htpc) and have it dedicated to the tv. I am heading that way myself. as i get the funds for the project, it might end up being a combination of
My Movies - Home
a slick addon to windows media center for a video collection management and library and gui setup.