To delete bookmarks:
Click the open-book icon to view your bookmark list.
The sidebar on the left shows collections, such as the bookmarks bar or other collections you’ve created. Individual bookmarks are listed on the right. If you can’t see the list of bookmarks because Cover Flow view is covering it, drag up on the handle below the Cover Flow scroll bar.
Select any bookmarks or collections you want to get rid of, and press Delete.
You can’t remove the bookmarks bar or Bookmarks menu from the sidebar. You can’t remove History and All RSS Feeds, but you can delete individual bookmarks within them.
If that didn't help, try maintenance...
From the Safari Menu Bar, click Safari / Empty Cache. When you are done with that...
From the Safari Menu Bar, click Safari / Reset Safari. Select the top 5 buttons and click Reset.
Go here for trouble shooting 3rd party plugins or input managers which might be causing the problem.
http://support.apple.com/kb/TS1594
If you are running Safari in 64 bit mode, try running in 32-bit mode instead. Right or control click the Safari icon in the Applications folder, then click: Get Info In the Get Info window click the black disclosure triangle next to General so it faces down. Select 32 bit mode. Also, (in that same window) make sure Safari is NOT running in Rosetta.
🙂