[reboot]

DON'T get any 3rd party software to manage RAM.
Just enable MS Windows Scripting Host (Control Panel > Add/Remove programs, Windows Setup tab, Accessories category, second from the bottom.
Open Notepad, and copy the following into it, and save it as "freemem.vbs" including the quotes!
FreeMem = Space(120000000) For 256 MEg of RAM or more.
FreeMem = Space(90000000) For 128 meg-196 meg.
FreeMem = Space(48000000) For 64 meg-96 meg.
FreeMem = Space(20000000) For 32 meg-48meg.
Put it on the desktop, or in the quick launch bar, and hit it once every hour or so. Takes a few seconds to run, but will free up the specified amount (or the closest to it possible) for use by new applications.
You could also put it into the Task manager to run once every hour or so.