Well .. if you are using the latest version (3.6.13) I know it is ok, as had about 10 tabs in it open last night.
Try Tools/Clear all history .. files .. cookies.
Try disabling add-ons .. one at a time.
What add-ons are you using exactly?
Are you using a custom theme? Try loading default theme and try again.
If all else fails, you will have to over-install.