Cheers for the link

. It was able to search my system and recomend a few options. Apparently the computer has four available slots with only one currently used with 512MB. It did recomend that memory is used in pairs for optimal performance
I think i my choice would be to go for 512MB x 4 or 512MB + 1GB x 2 (would 2.5 GB be much more noticeable than 2GB) Also, i had read somewhere that unless your really pushing the boundaries with software, then anything over 2GB is unecessary
Is it difficult to change the memory? can a pleb like myself do it? would i have to reboot everything, or at worst, could i wipe everything i already have on the computer. I have a reboot CD (at least i think that's what it is), all original software discs and i am happy enough to back up all photos/ documents etc in advance.
Thanks again
JD