Debian is the best distro, IMNSHO. Though I'd recommend Ubuntu for someone who's just starting with Linux, it has much better hardware support and non-free drivers, so you don't have to worry as much about force-arch-installing an i386 arch package onto a amd64-compatible processor, and going through 3rd party .deb archive sites.(It should be noted that Debian is the only distribution that I've used for any length of time, so this is extremely biased.)
If you choose Debian (and I highly reccommend it), go to these forums: http://forums.debian.net/ . For Ubuntu, there are many around. Fedora is probably the most popular distro, but I personally don't like it. There's too much of a RHEL-based environment.
Personally, if you don't mind a learning curve, go with Debian. If you like an easier ride, go for Ubuntu or Fedora.
Whew. Long first post.