In the Finder hold the Option key and choose the Library entry from the Go menu. Then go to the Preferences folder in the window that appears and remove the item called "com.apple.systemuiserver" from this folder. After doing this log out and back in, and hopefully the hangs with this menu will stop (you may have to re-add some of your items to this menu).
Alternatively, have you installed any third-party programs that put items next to these menus (things like network monitors, online drive services, or security software)? If so then try removing these to see if they are contributing to the problem.
If Topher's suggestion didn't work:
Try setting up another admin user account to see if the same problem continues. If Back-to-My Mac is selected in System Preferences, the Guest account will not work.
If the problem is still there, try booting into the Safe Mode. Shut down the computer and then power it back up. Immediately after hearing the startup chime, hold down the shift key and continue to hold it until the grey Apple icon and a progress bar appear. The boot up is significantly slower than normal.