I use winme, originally Ihad 128 and all my mem was taken often
upgraded to 256, good good, it didn't use the swap file at all most times but 160MB of ram was almost always being used, maybe 3~6hrs in to computer usage, at startup only 40~60mb of ram was being used. Then I bought tribes2 and it would read of the HD a lot, I also have a v5. Now I have 512MB of ram and Tribes2 loads much faster. Having a lot of ram helps a lot in win me if you keep your computer on for a long time and will be doing hardcore stuff like gaming or network/graphic stuff. If you're just gonna use it to type papers and check email, 128 will do.