Mouse Issue also...
Funny...I've had my Mac Mini for 2 days and on the 1st day I was using a Dell (wired mouse) with it. It worked fine for most of the afternoon then all of a sudden I couldn't get out of the finder window and the icons on the dock would not respond to a mouse click..
After rebooting several times and having numerous issues I was getting very frustrated and even thought about returning the Mini but as a last resort I decided to pull the Dell mouse off the system and plug in a wireless Logitech mouse and everything went back to normal...how bizarre...
So when I saw this post I was like hmmmmmm..I'm surprised I haven't seen too many posts on this issue...
It drove me crazy trying to figure out what was wrong...