UPDATE: the rainbow spinning beach ball appears for 10ish seconds every once in a while, but it goes back to the mouse and nothing seems to have changed.
So my MacBook pro is about two years old. It has a large amount of photo files but besides that, not much else takes up space. Today my system updates alerted me of a few updates available including iTunes. After the updates were installed it said to restart, so I did. When my computer came on...