I've used RedHat Linux, Knoppix Linux, a little bit of SuSE Linux but I currently run on Ubuntu Linux.
Ubuntu is a very user friendly OS, much like Windows but without the bugs.
It's all I use, you don't even need Windows.

You can use Wine to run Windows programs. Wine is an emulator so the Windows programs wont run as fast. But with Ubuntu, most of the software you need already exists within it.