If you're coming from windows I'd suggest mint as the differences aren't too great as far as the interface goes while at the same time you can get used to how linux works in terms of using the commandline and knowing the filesystem. Crunchbang is also great and preferable if you don't mind taking a bigger leap towards a different UI, especially if you have an older PC as it uses much less resources.

Once you learn the ropes of linux you need to figure out what exactly you want so you can decide your next distro if you want to move on to a more customizable and advanced distro.