Sometimes when I have too many programs running I won't be able to open a program, or when I do the graphics are all whacked out. Every so often, I get an error message along with it, something along the lines of "Low on system resources. Close a program before opening a new one."

I'm wondering if this could be fixed by a simple DEFRAG (which I haven't done in a while) or if I need to buy some more RAM, or whatever. What do you guys think?

i owuld say you need more RAM or clean out your startup as well. run : msconfig and get rid of the shit under start up tab u dont need, beware... if you dont know what it is i owuld leave it.