EMT or PVC Conduit For Exterior Above Ground Electrical Run
There are a few things you need to consider before running a long feeder and it seems you have at least given it some thought about method and materials.

First you say: 


  I am planning on running conduit along the exterior of my home to the
  wall nearest the garage.


The word "to" bothers me. Shouldn't it be "on". In other words you can't just run conduit on the ground. Conduit has to meet code requirements on securing conduit to something that doesn't move. So it needs to be strapped onto something so it doesn't move freely. There are different strapping requirements for each type of conduit and these can be found in individual articles in Chapter 3 of the NEC.

Also NEC code only allows 360 degrees of bends before adding a pull box this can be a variety of different types of boxes, condulets, etc. You will find you will need to follow these rules when you are trying to pull conductors as a 90 requires around 10 time more resistance than a straight pull. 

You can bury EMT but most contractors I know won't do it. Depending on the PH of your soil could cause the conduit to erode, sometime in less than a year. PVC is you best bet. Also most good contractors will always bury conduit at least 18" in the ground if possible. The reasoning being that anyone accidentally cutting a 60A underground circuit is not an experience anyone enjoys.

Good luck on your project and stay safe.