Which laptops will meet my requirements?

Check out this "Acer Aspire TimelineX" It will give you 8 hours battery life.

http://www.acer.com/timelinex/en-us/

6 hours of battery life is hard to find on a pc (if it says on the specifications up to 6 hours i'd say that it gives about 4 hours tops). My laptop at the moment said that it would give up to 4 hours but I get about an hour to an hour and a half with one program running with medium settings and brightness. You could always go for a used or refurbished mac book because brand new they are 999$ (if your looking for one for college they usually give discounts). I am american so I don't know what the equivalent is with euros.

But yeah, I have had a dell and atm using an HP. The next computer i'm getting is going to be a macbook pro probably because of the great battery life, aluminum body, great ratings and sexiness :D

You might be able to get all of those things for under 500 Euros except the battery life. In the most simple terms, you are going to have to spend a lot of money to purchase a really big and fat battery, but even then the max it might go is around 5 hours, and that's only for light work. I know you already said this, but if you are really keen on battery life...Mac is your best bet...sorry :(

You can always get a desktop, they run 24/7

confident, it meets the regulations, yet extremely. yet why do you have Visa and purely 1GB of RAM. this is gotta be quite difficult to handle...Vista makes use of two times the materials that XP does. If those regulations are made to make confident your computing device can cope with what's required, youll probable adventure fairly unfavorable overall performance.