PART 1:-
As VHG says, for your money, you will have a choice of any number of decent laptops. There will always be recommendations by individuals and from magazines for this make or that, but in all truth there's very little to choose between most of them in terms of performance. As long as you've got around a 3GHZ Processor, 2GB of RAM, min 160GB HDD and a CD/DVD Re-Writer this will be enough for most people. Assuming it's running Windows, Windows 7 is not necessarily a 'must-have'; indeed, you're more likely to see cheaper deails if they come with Vista/XP Home pre-loaded. Wireless capability comes mostly as standard, but double-check in case.
Where a lot of reviews/recommendations fall down is they often ignore the more 'minor' aspects which can be just as important:-
Screen Size: If you're going to play a lot of videos, get one with at least a 17" screen size.
Keyboard: Some well respected brands have real cheap look-and-feel keyboards. Get one with a keyboard that you like the feel of.