As you wrote laptop (rather than netbook) I assume you are after a screen of 12" mininmum.
Any specific plans for it ?
Any priorities ?
I'm perhaps asking vague questions but what I'm thinking of is that some people like to multitask, checking mail in the background while browsing, or playing music while using a machine for word processing, etc.
Some of the more recent machines have been 'cut down' to meet Microsoft restrictions (when MS wanted to stop supply of Windows XP, lots of people were still demanding XP over Vista, and machines from Asus and EEE were produced using linux or Win XP, but MS stipulated a maximum of 1 GB of RAM and a limit on the CPU speed, so these 'netbooks' and 'nettop' machines would be OK for streaming video or browsing or some other application but would not be ideal for multitasking and might be considered sluggish against machines running Vista (now Windows 7) costing 150 to 300 pounds more.
So - would Windows 7 be important to you, or would XP be OK ? Are you likely to want it to store oodles of files (so it would need a bigger Hard Drive for lots of video/TV shows) and would you want it to be used for primarily browsing, or more office-related work ?
If it seems I'm being nosy, it's only to get some idea - had seen a laptop on Staples in the sub 250 (+VAT) price bracket, but with only 1 GB of RAM, so may be slow for some types of application... IYSWIM