changed the scheme to mobile and cannot change it back
 

I clicked on my username, and was messing about with things there and changed the thing from 'Insignia' to something like VB mobile. Now everything's been rearranged, it's sparse looking and that little drop down menu has gone. I want to go back to insignia but can't figure out how. Any help with this will be much appreciated.

log off, delete the tfp cookie on your browser, and log back in again - you should have the default skin back.

That fixed it, thanks a lot.