Win ME has a serious memory leak. But other then that its just an enhanced version of Win 98 with a few other features and MANY other bugs and problems that seem to sneak up on you and bite you in the ass. I have had 3 computers run ME fine, no problems at all. It even seemed to run better for most things (these people didn't play games at all) then Win 98 did on the same system. But when ME goes, it goes with a bang. The only comp that I have had ME hurt was a old P2 233 with 64mb ram (This was a few years ago so dont laugh). Anyway ME caused some crazy Memory crash and forced me to format the hdd using a Linux CD I had. Even scan disk couldn't understand that there was a drive in the system until I formatted it with Linux. Dont ask me why but thats the way it happened
Anyway, I would say use ME untill you can afford to make the switch to 2k or XP. Most of the time ME will serve you fine, but from my experience if you play games get rid of it.