HELLO TO ALL! need some help uber noob!

[jedi79]

Ok well before i get my hands deep into linux mce i need some basic help 1st.... i installed linux mce as a hybrid being this is my pc as well and the problem is when i try to switch back to  ubuntu my screen is only in like the top left corner of my screen... and the resolution that i know works on ubuntu seems to be reset to a non working one and when i try to select my resolution that i know works in no longer an option in system>prefrence>screen resolutions any ideas guys?