2000 Professional Performance

I have allot of PC’sand Laptops with plenty of processor(500+), memory(128+), and disk space(8gb+), but they run quite slow after the upgrade or install of w2k pro. I’ve attempted shutting down unwanted services trying to tune without making it slower. I’m running office 2000, and mcafee av (scanning programs only) on all machines. Any advice or tips would be appreciated.