I'd like to give a plug for Red Hat.
I haven't played with it in several years, but I had downloaded several versions. Mandrake, SUSE and a few others also.
Around version 5 or 6 I decided to actually buy it from them. Mainly to get the printed docs. At the time, the version was a new release, and demand was high. They were not able to ship it when promised (I think it ended up 2 or 3 days later than expected). As compensation, they shipped a free book on some aspect of Linux. One of the shells or something..CRON maybe. I don't know. I hate loosing my memory
Whatever it was, it was a nice thick book, with a lot of pages and stuff!
I looked it up, and it sold for about $15.00 at the time. I think I paid $30 or so for the Linux. The book came with an apology from them, for the delay.
Anyway, I really thought that was a great, and in my case, unneeded move on their part. Really impressed me.
But then, it doesn't take much to impress me
Not saying buy Red Hat over free copies of some of the other suggested versions, just want to point out that IMHO Red Hat is a good company. If you decide to buy a package, might want to consider them.
And their free distributions aren't at all bad! Their RPM system makes adding on/Removing packages very easy, and I'm pretty sure KDE and GNOME are both supplied (GNOME is default I believe, but there is a KDE option if you use the GUI install).