Moving between distros I usually just have files I care about like documents and music on their own drive so I don't need to worry about moving them. As for moving from Ubuntu to Fedora, there are more steps to getting non-free software/codecs/drivers working on Fedora, you will need RPM Fusion for that. There are relevant How-Tos provided by RPM Fusion and other sources for installing NVIDIA drivers, ffmpeg (non-free), and more.