I'm trying to get above 4+ hours battery life

[stukpixel]

As it stands, I can only get 2 hours worth of battery life on power saver mode*. Though windows vista serves me well for my gaming purposes, I would like to consider trying to dual boot with a linux distro so I can use my laptop as a long life word processor.

This distro** would have to boot into a mode that should use 25% of my cpu at maximum***, and at most, 512 MB RAM. Under these settings, it should smoothly be able to use abi word, and browse the internet via firefox at the same time.

Now the my two questions, how would I go about doing that, and would it achieve 4 hours of battery life , plus the above criteria?
Please Help.

My laptop:
Gateway M-6827.

My Specs:
Gateway Official Site: Products - M-6827 Pacific Blue, Notebooks, Product Details
2.00 GHz Intel Core 2 Duo
3 GB DDR 2 RAM
Intel X3100 with 348 VRAM
15.4 in screen
1920x 1280 resolution (in vista)

*50% CPU, 6x Multiplier.
** I'm thinking Damn Small Linux or something fast like that.
***does that make a difference? my multipliers only go down to 6x

[gruven]

Honestly, with a 6 cell battery, you won't get much more than 3 - 4 hours with minimal usage.

The wireless card takes up quite a lot of battery, and you need to make sure you turn the screen brightness down all the way.

I used gentoo on my HP laptop with a 14.1" screen, and successfully got 6 hours out of my 12 cell battery.

Vista got 2 hours max on that. XP got about 4 - 5 hours.