I'm going to agree here with upgrading your kernel to AT LEAST 2.4.24. I have yet to upgrade to 2.6.X, but mainly because of my decent uptime, and the "It's not broken, it's not slow, it's fast, it's stable, leave it the **** alone untill prepaired to lose uptime" way of thinking on this box.

2.6, if you see a use you need it for, should be fine, but if you like 2.4.X, then stick with that, but get 2.4.24 at least.