Look at the inputs the TV has before buying it.    The input you use to connect your computers TV output matters a lot in terms of the picture quality.
RGB SCART (A European Standard) - Best.  It will allow the TV to be turned into an arcade monitor, when used with an ArcadeVGA or other card that can output 15Khz.
Component - Very Good.   A component is a notch lower than RGB Scart, but the picture is very good.   For this you need a card with component out.  480i or some times 480p is recommended for low res games.  Note that 720p and 1080i are very high res and widescreen
S-Video:  Gives acceptable quality for low-res games.
Component and RF give very low picture quality