Something I started doing was tacos-- cook the meat separate and it's easy to make a veggie/omni meal like that.
Speghetti was cool too- soy crumbles instead of meat.
I gained weight when I first went veggie (and then more when I went vegan, so I'm back to veggie) and it might have been because of the junk food I started to eat. So make sure she watches that.
For veggies- try stir frys with cashews over rice- so good! Teriyaki is nice and vegetarian, I never tire of it. Garden burgers work good in a pinch. I'm also a big fan of veggiewursts (vegetarian bratwursts) they're awesome.
It's hard at first to take the plunge, but once she's been at it (if she likes it) then it gets easier and easier!