Welcome and good luck. There are plenty of Linux distributions that come with desktops. Which one to choose.....? That's up to you. Check out this site
and this site
as a start in your search for "your" distro. If the first one you try doesn't suit you, try another. It costs exactly $0 to try (maybe more depending on how much your time is worth).
Don't, however, keep trying different distros just because the first one doesn't work. If you have problems, come here and ask for help. Give any distro you try a few months anyway.
There's a good chance that you'll bork something up at first. Provide a partition on your 120GB hard drive for backups. Backup your working system often. It saves a lotta time when you misconfigure your NIC and can't get on the internet. Not that I've ever done that or anything.