Which laptop to buy?

Check out Newegg, best place to buy laptops and you can easily search what you need. But I would go with a SONY VIAO.

i think dell xps 14'' can be suitable for your needs in reality i checked this laptop and it seemed to me really ok as configuration and even price is not as expensive as for other brands considering you can have 4 cores processor,500gb on disk,4-8 gb ddr3 ram at 1333 mhz and an high end graphic card as nvidia 2 gb dedicated and other features... If not you can consider an hp but they never convicted me too much as regards configuration or watch somehing from ibm/lenovo also in this case the price should be ok and may be configuration different depending from your choices...personally i am waiting after the ces 2011 and so the news in the laptop trends in this 2011 but if you need now i think xps cna eb a good choice for you!!

I suggest you find one that provide local warranty support, you see most would provide warrant but without local support you might take as long as two weeks before you would get your laptop back if you need repairs.

It depends on your budget, but the ultimate laptop out there is the laptop made by alienware. It is the most "powerful" in terms of CPU laptio out there, and looking at the specs you are after, you are either better off with a 360 gb hard drive, and buying a £20 external hard drive, or, you could think about investing in a pc instead. A bigger hard drive is more likely to break on impact (as it is basiicaly larger in size) and will also be heavier.