Can I Get a DWI While Parked in My Driveway?

Yes, this is what is called a physical control case. If you were under the influence of alcohol or tested above the legal limit, and in a position to start the engine and operate the vehicle, you can be charged and convicted of a DWI. It doesn't matter that you never intended to start the car and drive off down th street, it only matters under the law that you had the ability to do so. If you are in the driver's seat and the key is in the ignition,  you still have the ability endanger the public by driving under the influence of alcohol. The DWI laws are designed to favor protecting public safety at the expense of personal liberty.