Hi Tom,
Yes, you can achieve this using ARR. We also have documentation on how you can achieve this. Please check this link for more information. Also if you want to know more about then you can find more documentation here.
To server any file types locally and others from backend server what you can do is set proper url-rewriter rule which doesn't forward requests to server farm.
Let me know if you need more informatino.
Thanks
Himanshu