14.04 on VirtualBox is slow

I currently run 12.04 LTS in VirtualBox and then menus respond rather quickly. But, after installing 14.04 yesterday the menu is quite a bit slower to respond to clicks.
It works, but man it's slow. I have the VirtualBox display memory cranked up and it still doesn't help. Is there something in Ubuntu (window decorations) that I must turn off now?

Thanks for any suggestions.