Earlier this year, I tried Linux Mint 8, and had weird things happen, such as programs not appearing in the window list when I minimised them. So I used Ubuntu 9.10 Karmic Koala for a few months. As it turns out, this was most likely to be a problem with my hard drive - especially since it has a dodgy sector - not the software! I guess the HD didn't copy everything correctly when I was installing Mint.
More recently, I ended up mongrelising my Ubuntu OS, eventually trashing it in my attempts to remove a particular desktop environment, after much DE hopping. Since then, I've learned two things: 1. To work around my hard drive's problem by installing another distro I don't really need on sda1, setting up Mint with a dual-boot setup; and 2. To be much more cautious about what I cut and paste into the terminal, and why. (Not so much a danger of malicious code as of choosing inappropriate commands for the task at hand. No good fooling yourself that you're more clued-up than you really are.)
So here I am with Mint 9, still impressed at how user-friendly it is. Perfect for those of us coming across from Windows (or using Mint alongside). The aesthetics don't hurt, either (unlike Ubuntu 10.04 Lurid... er, I mean Lucid Lynx). What can I say? It just works... it's there in the background, functioning well as a means to an end.