Failed to load session "ubuntu" problem (maybe a error with Compiz?)

Failed to load session "ubuntu" problem (maybe a error with Compiz?)

I was fooling around in a program (I forgot what it's called) and I had
just seen a thing that made it so I could have multiple desktops at once.
When I decided I didn't want it anymore, I thought that I had put it on
from Compiz (since Compiz had options for the multiple desktops (called
Cube I think), and so I disabled everything with the name "Cube" in it.
I closed my computer and once I went to login into my account, I saw that
the bar on the side had disappeared. I went to restart and once I was back
at the login screen, I decided to go see if I had the same problem in the
Guest account. I went in it and the bar was still there, untouched. I
decided that I should uninstall Compiz because the thing that I
deactivated that caused the problem was from that.
I uninstalled it and when I restarted/came back on the login screen, I
entered my password to go onto my main account and I received the message:
Failed to load session "ubuntu". I then tried with my Guest account, but I
had the same problem on it too.
Now I'm screwed in Windows 8 and I'm wondering what I can do to fix it.
I've tried something about writing something in the command box that you
access by pressing Ctrl-Alt-F3 (the root terminal I believe). When it asks
me my password I write and I have a problem where it tells me that I wrote
the wrong password. I've tried it enough times to know that there's a
problem with the program.