Driving is pretty easy in Malta, but then we are used to 'that side of the road'. Pretty busy round Valetta. Buses are brilliant, cheap and easy to use so you could wait til you get there, see the lie of the area where you are staying and decide then if you want to hire a car. It should not be necessary to book in advance especially at this time of year. Where are you staying? Make sure you visit Medina. I am very jealous as we are hoping to return in September.