Ubuntu starts in BusyBox v1.21.1 and built in shell, help!

I’m new in this community and I really need help. I decided to start my computer as usual, got my hard drive divide in two, one part for Ubuntu and the other one for Windows. I choose the Ubuntu option during the boot, but instead of starting with the usual Desktop, it appears completrly black, with the BusyBox v1.21.1 built in shell terminal. Excuse my ignorance, but, is there a way I can recover my Desktop and all my files? ‘Cause I don’t have the Ubuntu CD with me, and don’t even have time.

Thank you so much.