How long will it take you?
My brother lives in Gib and has no interest in cars but might be a good excuse to pop over and see him.
Last year it took us an hour driving from Gib-Jerez. Left at 9, got there 10.30am (brekkie stop 1/2 way). 10 euros entry, or 20 euros for the main stand, which offers a good view of most of the circuit.
Lots of little towns dotted around the place for lunch too.