I haven't done the jeep safari, but it looks fun. If you're into that sort of thing I highly recommend Megafun - they are based in PDC and do a quad trek which takes in half the island, mostly off road - really, really good fun. If you have kids they can travel on the back with Mum and Dad. See more at
http://www.megafun-lanzarote.com
http://www.grupoestupendo.com