If she is deported, or if she leaves voluntary after having been issued a final order of deportation, is there any way she would be able to return before the 10-year period is over?
Unlikely. You would need to prove that her deportation constitutes a severe hardship for you. It doesn't sound like you've been married long enough to be able to show that.

What forms would we have to file, and how likely would success be?
She would need to file the I-212 after her deportation. Processing takes 6 - 8 months, and no one can tell you how likely approval will be.