Hmmm... 2 things that may be completely way off but:
1.) Win ME... (LOL)
2.) WD hard drive... (sigh - possibly flakey)
And although they claimed they fixed it, there's been some uptime buggaroo in windud where it resets it's uptime clock every 49.7 days or something I believe? Don't know if that's really what's impacting you but still... 😉
Basically, 9x/ME weren't made to stay up that friggin' long. And ME is known to have so much sh1t running and trying to keep itself going that I wouldn't be surprised if you may need to scandisk and/or defrag (plus look out for that swap file it has)
My 2K advanced server has been up about 85 days, and that's amazing in and of itself... but it's supposed to be a server... 😉