Sooooo this will get mentioned at some point so may as well do it now...
Why not just buy some £30 or so 2.1 logitech speakers? You'll get infinitely better sound and its not significant money. The speakers would plug into a headphone socket if the TV has one. If you don't have a headphone-out and use SCART/composite then a few pounds worth of adapters/splitters/gender-changers etc from ebay will have you hooked up. If you're using S-video well then just get with the times. If you're using HDMI and don't have a headphone-out well then you're probably stuffed unless the device (e.g. PS3, which btw does...) is pretty flexible and can route video down the HDMI and audio via a different output.
Or you might just want a new TV. In which case, fair do's. Obvious consumer pitfalls is the whole HD malarky. HD is 720p but this will most likely come in the 1280*768 form, 1080p is "full HD" which is obviously better. 720i or 1080i equates to roughly halve in theory so avoid that. Unlikely to be much tech spec on speakers so only hope is go by reviews. Consider inputs/outputs. How many devices you have, what type. Do you plan to buy more HDMI devices in the future etc.
(how do you spell "fair do's" btw? because the ' is obviously wrong but "dos" just sounds like I hang around with people who like hitting vtec y0 on 1.2 clios with RS badges?)