22" monitor £100-200

It would help if you filled in the template: http://www.tomshardware.com/forum/59847-3-template-monitor-advice

However, a few things to point out:
1. manufacturer quoted response times aren't always calculated the same way, so I advise against using them for comparison - even if the monitor has a quoted response time of 12ms, this may not actually translate into significant ghosting. You're better off looking at reviews that show the response times for multiple transitions, such as the ones at X-bit labs, or at least at ones that compare photos that show how much ghosting there is (and the inverse ghosting that some monitors have, mainly the ones that claim 1ms response time), like at TFT Central.
2. LED backlighting only has one confirmed advantage, which is that the panel can be thinner. Power consumption isn't always significantly less, and it can have a blue tinge, because inexpensive LED backlights simulate white with a blue LED and a yellow phosphor.

Image quality is usually a big issue if you're doing photo and video editing, but not so much if you're gaming. If you really want to keep ghosting to a minimum, the Samsung SM2233RZ is the model that TFT Central considers the best at that, and it's in your price range, though being a TN panel, the image quality probably wouldn't be as good as a Dell U2211H.

Cool, i was looking at the SM2233rz, I found a lot of people have had problems with flickering with ATI cards in 120hz mode, and as I'm running a hd4850, this could be a problem.

Also is the Dell monitor you mentioned one of the best for image quality?

The Dell UltraSharp series tends to offer a good ratio of quality to price. I think there are monitors with better quality, but they get more expensive very quickly.