It's not mentalray that's crashing, it's actually a part of Maya regarding geometry. Try running the mentalray diagnostics, and see if it pops up any warnings. There is so much geometry going on in my kitchen... I tried eliminating all geometry piece by piece, and nothing is working. I even literally deleted all the geometry at once in the entire scene, rendered with mental ray with nothing in the scene at all. I even removed all nonmanifold geometry and it still crashes...