Ubuntu or Mint (which is based on Ubuntu) would probably be the easiest "just works" distros. I'm told Mint is preferred for people coming from a classic Window

Ubuntu or Mint (which is based on Ubuntu) would probably be the easiest "just works" distros. I'm told Mint is preferred for people coming from a classic Windows background but your mileage may vary. Fedora would be the other major contender. It's developer friendly and pretty easy to use. One thing I would mention is that they take a stronger stance on most open source software so you have to add the RPMFusion repository if you want to use closed source software that's excluded from the main repository. Fortunately this is not difficult. The great thing about all these distros is that you can get LiveUSBs so you can try them before installing. I'd highly recommend doing this.