Which Laptop (£800ish)

Im looking to spend about £800 on a laptop to add some portablity to my aray of PCs!

Ive never had a laptop before, so im not quite sure what i what, or what to look for, so im just looking for some advise really.

Things i'd be using it for are:
- Taking on holiday to support my digital camera, and to print off sheet music for our band as/when its needed.
- Taking aboard our narrowboat to check emails/forum (wirelessly), watch DVDs, as possably also play music (mp3's etc, ie winamp) when we're crusing and the engine is charging the batterys.
- And then when we're at home, it will proberbly end up in my sisters room, where she well mainly use it for surfing the net and msn (via wifi) and possably also play the Sims...

I dont want to be too huge, but at the same time it doesnt have to be uber-portable, and i'd prefer it to be fairly robust than feather light and fragile.
- Almost anything will do for the digi camera thing, and a the sheet-music program (mozart) is also not very hardware demanding.
- The main problem on the boat is power, as everything is run off 4 100Ah 12v batterys, and i can light the whole room with only 11w! And theres currently no 240v onboard unless where pluged in! (although i could get a small inverter...) So ideal it wont use to much juice.
- Im not sure what the minimum spec for sims is eather, but im sure its not nothing!!

Also, i dont think i want a wide-screen.
- What about a Thinkpad, and can you get 12v chargers (ie, as you would use in a car)

Sorry for the rather waffley post, but im just trying to think it all though!

Thanks, Daniel