I had to deal with that problem too for a long time. I first used RedHat up to 9 but for some reasons I got in trouble with updating from redhat need to register etc. etc. And also only security patches.
After a while I moved to debian, and I will asure you they have the best package / updateing system ever!! The only disadvantage is that it's community driven, there is no Company behind it. Every month I run a comple of commands to get my system up-to-date.
Debian has three types stable (mostly for servers), testing and unstable. For example in stable there is only apache 1.3 and testing contains apache 2.0. If you're running a server I would suggest stable and if you're running as workstation I would suggest testing or unstable.
installing, removeing and switching is really easy with the apt-get command. If you're going to use debian don't try to compile programs from scratch if they need to be updated frequently because debian can't do that for you
The big disadvantage of debian is that it's not a easy system to learn linux, a little linux experiance is required!