This is going to be my first pc, so my budget is £350, ideal size would be 11.6" or 13.3", but 15.6" is the max size i'll go with, has to have 6gb ram or more, hard drive has to be removable/changeable if it's anything below 750gb, optical disk drive not needed, but wouldn't hurt having it.

url=[click here Satellite C850-1NU[/url]

or

url=[click here Pavilion G6-2242SA[/url]

Also if possible, can you explain why one is better than the other, my main purpose is to multitask, for example watching a youtube video, playing music in the background, browsing with many tabs open, whilst editing videos (this is minor editing, like i'll use it once every 3 months to cut & join videos with windows live movie maker) etc.

Another thing if you know of something even better, then do tell.