Hm... I've used too many Linux distros
A distro I just installed and have found very nice is Sabayon Linux. It's very easy to use (not very popular for some reason) and very nice with a large package selection and comes with 3D desktop effects built in if your video card is supported. It's also got a (on the install CD) a Quake 4 demo, full desktop mode (so you can give it a go before installing) and a partition editor.
Assuming you are using Sabayon:
*Download it from
http://sabayonlinux.org/
*Burn the ISO to a CD
*Boot into it (choose desktop mode or install..) You can enable the 3D effects on the live cd/dvd if you want, but it slows things down
*Open the Partition Editor (if there is no icon, press Alt+F2, type 'gparted' in the box that opens, and press 'Run')
*Resize your current partition and then create a new one (at least 10 GB) in the free space (see the help menu) and consider making a swap partition (sort of like virtual RAM, should be around the same size as your RAM, larger if you have the space)
*Open the installer, and in the partition selection screen, your new partition should be sda2 (for SATA disks) or hda2 (for IDE disks) and read the help if you need to. You can reformat the new partition if you want but if won't get you very far.
*Boot into your new Linux system
But as a warning, don't install any graphics drivers (ATI didn't work for me). I did and the display is messed up
But if you don't want to get Sabayon, I use OpenSuSE as my main system and I find it very nice. But the installer isn't the best for new users. And yet another great distro is PCLinuxOS (pclinuxos.com). It's the best distro I've seen for new users and is even good for advanced users.
I can advise you against Ubuntu because you won't get very far with it. I had it installed for a while but it made everything more difficult. It came with hardly any programs and the package installer has a very clunky interface (plus it took me ages to find and figure out. It doesn't categorize apps very well) so you can't easily accomadate for the missing packages.It's doesn't even come with basic GNU tools...