I would highly suggest either SUSE, or Redhat simply because of the ease of setup and the ability to have automated updates via the internet.

I mention suse because of the large amount of software that comes with it, i mention redhat because it is becoming the world standard in Linux, and the RPM system (redhat package manager) is awesome.
im a linux user who knows quite alot about computers(i build them for a living) but not jack-squat about programming, so one thing that is important to me is to be able to have a distro that will automate the update process and not require me to build and compile source code to make new modules, etc.

I started out on debian, it is nice, but when i went to search for software fo tit, i found that all of the binaries were either source or rpm packages, so i went with redhat for a long time. fedora is a great project, like redhat but instead of getting redhat's official support, you get a million worldwide user's support.
as for what system i think has alot of potential commercially my vote would be for two not so linux distro's - SCO, and Solaris, they have both come quite a long way in terms of ease of use.

I voted for Mandrake

Reason:
It worked for me of the box install went smooth, the only thing i had a problem with was what linux users have trouble with the dreaded Winmodem.

now before Mandrake i tried Redhat 5.0,Debian,Suse 9.0 and i had various problems with them but not always the one.

with suse 9.0, it was compiling programs, no matter how i tried, it simply would not compile most source code for me with the normal commands make,make install ect.

Now with debian i would get it installed and have trouble getting it to use my Video cards 3d accel functions, most of the time i could not get X up and running at all, and configuring my modem was a pain even with the drivers.

then there was Redhat 5.0 damn thing would not find anything it seemed, well okay my old video card but that was about it,

then i quit using linux for a while thinking it was not for me at that moment in time so i read up a little on it and found that unlike most operating systems, linux is constantly evolving and growing all the time and becoming much easier than before so i gave Mandrake another shot 10.0 and have been happy ever since.

so for a newbie distro i would choose Mandrake, and i would know i am a newbie still and always will be

Rusty_L

Well I would say Ubuntu is a good start if you want to LEARN about Linux. Mandrake doesn't allow you to learn much, it just takes over like Windows XP does.

Ubuntu 5.04 Hoary WORKS AWESOME. If your wanting to use WineX/Cedega/Point2Play I HIGHLY suggestion this distro!

Not to mention Ubuntu 5.04 has ALSA 1.0.8 by default, all my sound worked for the 3 cards I have. SB Live X Gamer, SB Audgiy LS, VIA onboard.

Good luck with your distro quest!

Please note: Ubuntu might not be for everyone, but its worth a shot.