Stuck on grey screen after boot, Disk Utility says HD is OK
Today my 2010 Macbook Pro 13" running Lion suddenly stopped booting up and remained stuck on the Apple logo and spinning wheel indefinitely. It does not even go to the login screen (but does in certain circumstances as I will detail below)
Here is a list of things I have tried already!
Hold Shift to boot into safe mode:
The progress bar goes about halfway and then stops and goes back to the spinning wheel again.
Hold Cmd and R to go to Disk Utility:
In the Disk Utility I repaired and verified permissions and the disk and the results come up as OK.
Hold Option to select drive:
When I do this, and select Macintosh HD, it takes me to the login screen and I can enter my password, however upon doing so it brings me to a crashed Chrome, which gives me the option to Restore previous tabs. Nothing else loads and a grey screen remains in the background. No dock or desktop or Finder appears or works. I can get into System Preferences, however I can't connect to my Wifi network even though it is detected. I can connect to Wifi when I am in the Cmd and R Disk Utility mode though.
Resetting PRAM/NVRAM and SMC:
I have tried these and none of them make any difference to the problem.
I would appreciate it if anyone else has any ideas I could try.