The only one that anyone would realistically be able to operate is the delorean.

The Tardis is very complicated to use and has a mind of its own, trek ships have huge, highly-trained crews for maintenance and general operations and require futuristic technology and components to be replaced every so often, and the stargates require massive amounts of energy and require you to have the gate coordinates of where you want to go.

The Delorean is just get in the car, choose a time and date, and go.

In principle the tardis wins because you can go anywhere at any time, but let's be real... most of us would actually die trying to fly the tardis somewhere.