Winter Storage. What to do with/for front tires?

If you've got the rear end up on jack stands then also consider doing the same for the front end. That way you don't have to worry about flat spots.

As someone else said, unless you can get the engine up to operating temperature for a while and vary the engine speeds from idle to 3,000 rpm, it might be better to not run it at all during the winter. Running the engine under no load for 10 minutes every week at idle will lead to condensation in the oil (there's a very recent thread about what that does inside your valve covers) and will also drain your battery so it will likely be dead by spring time.