Suse at the moment, though I first flirted with linux at mandrake 4 or 5, I think, tried various distros, mainly from the LF cover cds, Storm is the only one I can remember liking a lot.
Bought Caldera Opendesktop2, then suse 7.1 Pro was bought for me as an Xmas gift.
Was a Mandrake Club member from 8 through 10, then jumped ship for suse 9.
Presently Suse 9.3 64 bit on my home desktop, lots of suse at work.
I have always liked Suse for clarity and the manuals are always good, the money Novell are pumping in seems to be producing a good return.
Mandrake always seemed a little cuter, Debian was just hard work, Redhat (especially the KDE desktop) always felt a little unfinished and restrictive. (these are personal impressions, not detailed evaluations).
Knoppix is cool, Smoothwall does it`s job well, Clarkconnect and Esmith deserve a mention.
I think the best way is to choose something that you feel comfortable with, and stick with it, learn what you can, until you see something that you think will work better for you.
The thing is that some people will like minimalist, some want eyecandy, some just want to get a job done.
At least in Linux, you have a choice, whereas the windows world is trying to cram the same product onto every piece of computing hardware available, from phones to servers!
The sig between the asterisks is so cool that only REALLY COOL people can even see it!