I crushed a ball point pen in the arm rest storage case and the ink has spilt over onto the vinyl/leatherette. What can I use to get it off without smearing?

White vinegar and water--50/50--is probably the safest thing. Blot, DON'T WIPE OR SCRUB, with paper towels moistened with the solution. This may not remove all of the ink, but it should lighten the stains considerably. Don't use solvents as they could soften or discolor the vinyl.

Once you have removed as much of the ink as will come off using the above method, you might try Vinylex, since it won't harm the vinyl and may remove additional.

The likelihood is that you won't get all of the stain out. Ball point ink is one of the nastiest stains to remove from ANYTHING.