Disk Utility (recovery mode) stuck at loading
A solution for getting the disk utility unstuck is opening Terminal and running this:

sudo ps ax | grep hfs


You will see a line that looks like this:

**970**   ??  U      2:08.88 /System/Library/Filesystems/hfs.fs/Contents/Resources/./fsck_hfs -y /dev/disk2s4


Take note of that first number and run this:

sudo kill -9 970 # (use your own number here)


The Disk Utility gets automatically unstuck. If your hard drive shows up, but the drives are grayed out, try restarting into Recovery mode (pressing Cmd+R after booting). After a couple of restarts you might be able to finally run First Aid on your drive.