Starting emulator for AVD 'Android_2.2' PANIC: Could not open: Android_2.2
Are you starting Android Virtual machine from within eclipse or directly ?

If you are running it from eclipse then before starting eclipse just make sure to run the below command:

sudo export UBUNTU_MENUPROXY=0


Now start the eclipse and try running AVD from it. 
I hope this helps. It solved this issue at my end when I faced the similar problem.