I got a Toshiba back in 2002. Got 512 MB of RAM and a 2.4 GHz Mobile Pentium 4. Windows XP got slow after the years, so I put 7 on (lol Vista). 7 was clunky, but it worked. I had to restart it occasionally just to clean it out.
Put Windows 8 Consumer Preview (Release Preview requires bit execution which the proc doesn't support), and it runs really smooth! Geekbench score went down (I assume dark magic was involved) but usability is through the roof. I can leave it on, play music, and search stuff for as long as I want. Yay. Upgrade? Pshaw.