Safari screen turning grey

How often do you "restart" your machine? You may want to try doing a safari reset:

http://support.apple.com/kb/PH11914

Might be a cache issue.

Open the Finder. From the Finder menu bar click Go > Go to Folder

Type or copy paste the following:

~/Library/Caches/Safari/com.apple.Safari/Cache.db

Click Go then move the Cache.db file to the Trash.

Quit and relaunch Safari to test.

I gave you the incorrect path.. my bad.

~/Library/Caches/com.apple.Safari/Cache.db

Make sure the startup disk is ok.

Launch Disk Utility located in Applications > Utilities

Select the startup disk on the left then click Verify Disk then Repair Disk if necessary.

Salut indoscot

install the current version of Adobe Flash Player and your problem is probably gone.

Cheers

Andreas