By the way, I've noticed that most people in this forum use Ubuntu rather
than Mepis. Is there a good reason for that or just a preference?
Think of it as a Family tree with (correct me if im wrong) Slackware (since it uses source files) as the Partriarch. Down one leg (the .deb leg) it would go Slackware->Debian->Ubuntu->Mepis. each one is a descendant of the the one before it. All these use the same repo file type (.deb) except for Slackware (tar.gz.src ,or something like that). Ubuntu has been building a reputation as being a user friendly distro for some time now. It is growing into its prime and alot of people are pleased with it (the current release that is). Ubuntu has been growing a solid user base (such as myself) who like to be able to do simple things with a GUI for speed but not have the CLI taken away from them (as some distro somewhere has tried to do Im sure)
The other leg of the tree is the RedHat (rpm) leg which goes Slackware, RedHat and then its offspring Fedora, Mandravia, SUSE, and so on ( the RedHat leg has more branches then a 1000 year old Weeping Willow and most stem directly from RedHat which makes it very hard to explain).
I personally have not tried Mepis (yet, but it is on my list) and would say that if you are happy stay where you are. if your bored try the Ubuntu Live CD, or the Fedora 7 Live DVD or any other distro you see that you think you might like (there is one I will suggest just for a change of pace with the GUI its called Symphony OS
and while buggy is very differant from the other GUIs GNOME and KDE it uses Enlightenment, I think)
Try any distro you chose you will find some you hate and maybe one you love more then your current one.