Different distros come compiled with different software, package managers, desktop interfaces, etc. It's really a subjective thing, as suggested here before give a few of them a try in a Live environment and see which one peaks your interest the most. If you are new to Linux, distros like Slackware and Arch may be a little complicated at first. I think the best for newbies at Linux are distros such as Mint, Ubuntu (and variants) and Zorin to name a few. At the end of the day, it's up to you!