Why isn't desktop Linux "finished"?

I can see the reasons for going with KMS and it sounds like it works for you - however I'm now having to make another trip to upgrade from 10.04 LTS, to solve the "freezes every day or two" problem, which I'm guessing is KMS related though it's hard to tell.

The 10.04 LTS upgrade has been a disaster, the person using has said she wants to stop using Ubuntu as a result. Hopefully going to a more recent Ubuntu (maybe 10.10) will fix the Intel KMS problems.

Can anyone recommend a good Ubuntu or similar distro version (Mint, Mepis, Debian, with reasonably quick security updates) that has KMS working well on Intel GMA3100 or similar, without random freezes? I don't want to try getting a newer Xorg and kernel working on 10.04, as the idea of this PC is to be low maintenance and reliable for the next 2-3 years.