LOL, I think you mean a harddrive? Like memory to store stuff? If that's the case, you need a new harddrive. QUite easy to install and you can find them at most any computer store
V-Mem is a bit of space on your harddrive dedicated for RAM usage. Most computer don't have a enough ram to run programs. Say a prog requires 300 megs, and you have 256M system ram. You're computer will take the difference and use some of you're harddrive for it.