boot error since i installed beryl

my story: i had ubuntu dapper drake running perfectly fine. then i installed beryl. i wasn't able to use it but i have it on my toolbar. when i configured it, the buttons disappeared so i rebooted. since then my OS boots but only the default desktop image and the mouse can be seen. please help! i don't know how to reboot/shutdown from there so i just force it off by pressing the power button.