which one should i use, ive been trying linuxes for about a year, but i guess im still a noob, but yea, i installed ubuntu and its pretty good and easy to use, but i have a friend that uses gentoo and he says its really good, and i have heard good news about fedora core, so which one is the best (or the better out of those 3)? (im willing to learn just about anything to have the best (or better of the) operating system(s))