Programs won't install in Win2K

[Wildnites]

I'm trying to fix my friends older PC. It's a Compaq (c. 2000) w/ a PII Proc., 5XXMB RAM, Win2K Professional. All he does is web surf/email/burn CDs/DVD so he's got enough for his needs right now. This problem has recently developed, programs will not install. I tried installing the Win2K service packs and the files begin to extract and then----------nothing. No, hourglass, no error or info messages, no splash screens, nothing. The installation process just halts. Just out of curiosity I tried installing other programs like an adobe reader, same thing--- the installation process just ceases without any messeges or info. When this happens I still have total PC functionality. I can open and close programs, see the mouse cursor, use the keyboard, etc. and I was able to install a few programs on it last week so the problem appears to be a recent one. Any suggestions on what kind of problem this is and how to go about correcting it? Thanks!

[flanzig1]

Check to see if the HD is getting full. If OK, run an HD diagnostic program to check the health of the HD. Also, do the same for the ram. Memtest is the program to use on ram.