Striker: as sunnystaines said, for anything other than basic office productivity and net surfing applications, a netbook will always struggle. For sure, as a minimum, gaming and watching movies will eat up your battery. And because netbooks typically have only the most basic of graphics capabilities (even though they say they'll play HD movies) they will never be very good at graphics-intensive applications.

The best I can tell you is, I've had experience with an Eee 1001 and an Acer Aspire One D257. The former is a 1GB memory machine but because it's running XP, it runs pretty well. The latter also had 1GB of memory, but it was a W7 machine. Even though it was stripped down, cut-to-the-bone W7 (i.e. Starter) it ran like a 3-legged dog. However, I upgraded the memory to 2GB (there's a thread on it here somewhere) and it now runs much better. But, like I said: I've never tried gaming or watching movies on either, largely because I think they'd likely be rubbish.

To do what you want to do, I think you're looking at a small laptop - and with the graphics capability you'll need for movies and games, it won't come within your £300 budget.