Finder keeps freezing I have a late 2013 Mac Pro (running Yosemite) and have had some problems with a frozen finder recently. When I select a tif/pdf/jpg file it freezes up on me and I have to force quit it. It freezes before it is able to splay the thumbnail of the file I have selected. It sometimes also freezes safari when I click on links or download something, although its a much more frequent problem for my finder.

Any help to get around this is appreciated, its a really annoying problem!! 

Edit: spotlight also now freezes but my activity monitor is suggesting all is well
Check the Task Manager to see if anything (like Finder) is hogging Memory or CPU cycles, and check the disk activity as well.