With two Gigs of RAM I doubt you'll use it all

I was curious with XP when you go to the memory settings you have "initial" and "maximum".
Most articles I have read lately say to set the minimum at 256 MB and "all available", I don't have those settings.
Am I correct in assumeing that "minimum = inital" ?
And as for "whatever available" how do I know since free hard drive space is changed every time I'm on the computer.

Would this work?

Initial-256Mb

Maximum-1152Mb (or something like it)