Hey man, try a DVD! It will probably look pretty good. The problem is that TV's have very low resolution compared to computer displays. NO TV-out will give sharp text or even readable text unless the text is larger than 18 points (assuming 800x600 PC resolution). And things like menus, icons, etc. will definitely look fuzzy on the TV. Plus, only the Matrox G400 dual-head and ATi cards using the Rage Theater TV decoder chip have halfway decent TV-out, the rest are pretty mediocre. But DVD movies should be at least OK no matter which card you are using. Oh, and composite (RCA-type connector) video is kind of fuzzy compared to S-video, but you gotta go with what you have.
Also, adjusting the brightness, contrast, and color saturation of the TV-out, if those controls are available through the video card driver, could help somewhat. But you'll never want to surf the web using your TV-out! DVD's and games can look pretty cool, though.