TV screens only have to show up to 625 lines, monitors have to go to 1280 to support the higher PC resolutions. Dual monitor/TVs should be to the higher standard to support both. Some cheaper models will only support one mode at a time, so watch out if you want to use both at once. You will need one that supports Picture in Picture (PIP) where the TV can be opened in window over the PC display and vice versa.
PCW recommend the Dell W1700 as their best buy, but looking at the Dell site it seems to have been replaced by the Dell W1900, quote:
The Dell TM W1900 19" (48cm) LCD TV provides a terrific TV viewing experience. With 1280 x 768 resolution, it is optimised for DVD, today's standard TV signals, and tomorrow's High Definition broadcast standards. The Dell W1900 19" (48cm) LCD TV also includes full picture-in-picture capabilities so you can work on your PC and watch TV at the same time.
Shop around for something similar to your size and taste.