Your running Vista with 256MB of ram? That must be painful. Visit
Crucial.com to find the memory you need, it's very easy to upgrade on most
computers (you failed to say what you have).
Go to Computer, right click your drive and select properties to see info on
the drive.
Are you sure that is correct? Are you sure that is not the amount of video
RAM you have? You can go to Start > Control Panel > System, and it will tell
you the amount of RAM you have. I can't see a manufacturer releasing a PC
with 256 MB of RAM with Vista (that's lower than the required amount).
Also, you can go to Start > Computer, and it will show your drives with the
size of the hard drive, as well as the free space on the drives.