My ground for the main electrical panel is located where I want to place a shed. I need to move about two fee in the other direction. Can I just throw the main circuit breaker, unhook the ground wire, pull the long ground rod, relocate, reattach and throw on the main breaker? Anything else I should be aware besides making sure the connection is tight as is now?

Yes, if the ground wire will reach the new location. Ground wire must be one continuous wire, cannot be spliced. Not necessary to turn off power if you are not going into the circuit panel.

You are not going to pull that ground rod by hand. Cut it off and get a new one.

Any time a grounding electrode conductor, the wire that connects to a ground rod. Is disconnected, the power should be shut off, as this wire could be carrying fault current.

Simply drive a new rod, check with local codes, as some locations require a min of two rods, and connect the ground wire from the panel.

If the ground wire is too short, will need to run a new wire. If it only connects to ground rod, it can be a minimum of a #6 copper wire.

HK is correct, a grounding electrode conductor must a continuous wire with no simple splices. Of course there are exceptions, any splice must be irreversible. This is done using a compression crimp or Cadweld exothermic connection. Both methods require special materials and tooling, Simpler to just install a new wire that is long enough.

Any splice