Hello:)
Sounds like a JavaScript error happening. Could you fire up Google Chrome and open the Web Inspector to see if anything jumps out at you in the Console and report back your findings?
If so, I would be far more enabled to help you once we have that information :)
There are many things that could cause this, but from what you're telling me both the main menu and the toolbar isn't working, which means that the joomla js and ninjaboard js is failing. Those js files are very different, but the menu js is loaded after ninjaboards.
I don't know if the error happens before or by the ninjaboard js, but since the menu js fails to that means the error is a global one.
Global errors means they happen outside any functions, which makes it a bit easier to hunt down as very little of your js is running in a global context.
Usually this happens if you load two different versions of mootools at the same time for instance, or if some js that require mootools are loading before or without mootools itself. Causing a fatal error due to a script trying to use variables that don't exists.
Could you tell me more about your new server setup? Like Joomla version, PHP version, wether mtupgrade plugin is enabled or not, if you have any non-standard system plugins enabled or a non-standard admin template.
Thanks