First and foremost, debian ROCKS!! Never used it before this, but they have won my heart over and I might never use another distro again!
*ahem* anyway, my general opinion is that you should go ahead with 2.4. I've used it and it rocks for a personal OS... You know: gaming, word processing, browsing the internet, etc. Its BY FAR more stable and secure than any Winblows OS could ever hope to be.
I should mention, that before 2.4.18, I would have used 2.2 anyday. But we are sitting at 2.4.22 and 2.6.0beta is out now.... I think its more or less getting time to lay 2.2 to rest, and move on to the next millenium of linux :-D
As for servers (where sercurty and extreme stability are a must), if you are really paranoid about it, go with 2.2. I cannot deny, that it is tried and true... But I still think, that by now, it will be ok to go with 2.4 as long as you go 2.4.2x... Anything b4 that might still be a bit untrustworthy for a server application.