I heard, though I didn't try to prove it myself, that most computer equipment, including the screens, are dual voltage appliances. There is a toggle switch either on, or maybe even inside, the back panel of the "box", and on the back of the screen. Have a good look over your computer to see if you see any switches.
Having said that, if your machine is more than a couple of years old you may want to take the opportunity to upgrade!

TV and video equipment is particularly problematic as the the voltage,
and the frequency of the mains is different,
and the TV system is different. So, I'd forget bring TVs and videos.
It really depends on how many appliances you have as to whether it is better to bring them and buy transformers, and have the nuisance of moving them around from room to room (I presume that you won't be buying one transformer for each appliance), or to buy cheap appliances in the UK and chuck them when you return to the US. Try looking at
Argos as they have a good range of household electrical appliances, and some of the best prices; not always the premium brands, but things good for a few years.

Bear in mind that anything with a motor, other than CD and DVD players, will run 17% slower in the UK as the mains frequency is only 50Hz as opposed to 60Hz in the US. This problem may affect tape players, but I'm not certain as I have heard that some
may have speed governors independent of the mains frequency ..... and mine are still in storage.

If you need transformers for anything I suggest that you buy in the US - I found
DVD Overseas to have particularly good range, and buy larger transformers than the minimum you need, especially for HiFi equipment which is sensitive to distortion that may be introduced by a transformer straining at it limit.