I haven't checked out the other Linux distribution but yes, Ubuntu has a very good support forum. My first installation had no hitch. Actually it was a Wubi installation then a migration to an open partition. No problems.
Then I installed on an older Dell. Complete installation from scratch creating the partition (Dual Boot with XP). I did run into minor glitches but the support forum sure walked me through the troubleshooting process.
I suppose other Linux distributors has just as fine as support forum too but just posting my experience with Ubuntu.
Yes, I would suggest people use Ubuntu or other Debian variants if they are new to Linux...
Linux Mint is based on Ubuntu, so is Pinguy OS.
Xubuntu is basically Ubuntu with a different desktop environment (uses XFCE not GNOME) and is intended for older systems with low processing power/memory.
Optionally, I think Fedora can good for new Linux users. Fedora variants, however, use YUM package installers.
FYI, most things tend have support for .deb installers (which is a Debian package installer for installing software). YUM has a lot of support too though.
I'd get some Live CDs and try some of them out. (Remember, Linux Live CDs are incredibly slow, Linux isn't slow once you officially install it to your hard drive).