Hi, I'm headed to Sicily for a week in May with my girlfriend, and I was wondering whether it's easier to rent a car to travel or to rely on buses and trains. I've heard that it's a pain to find parking in the major cities there, and that rental cars are often broken into. Any thoughts?

Staying in Palerma, Siracusa, Taormina, and maybe a side trip to Agrigento? Then use trains. Wanting to explore the back roads and small villages? You'll need a car.
We've done it both ways, overall I'd go for the trains.

We rented a car in Sicily and would not do it any other way. In all major towns, there were plenty of well-marked lots and even when we had to pay, the daily rate was about 2.50 USD. I love the freedom to travel when and where I want--you just can't get that with public transportation.

i agree with patrick - the "best transportion" depends on your travel plans.
friends and i just returned from two weeks in sicily. we stayed in palermo for four days, and walked or rode the buses. we then took the train to cefalu (barely an hour away), where we stayed in the historic center and walked everywhere.
in cefalu, we picked up a rental car to drive to our week-long vacation rental in taormina. once there, the car (a lovely alfa romeo sedan!) mostly sat in the parking lot - except for day trips to catania and siracusa.
good luck with your plans - it was my first visit to sicily, but it won't be my last.

Was happy to read Patrick & italy4me threads re: trains...We will be in Cefalu for 4 days...We will be 7 people...we have a van, but wonder if it would be better to take the train into Palermo..Is the Palermo station anywhere near the Cathedral and Teatro Massimo?

Re Palermo-Cefalù train, I answered here: http://www.fodors.com/forums/threads...p;tid=34503509

The train station is not right near the Teatro Massimo, but it's an easy walk, if you're not carrying luggage. I walked to/from the train station from about twice as far away the day that I took the train to and from Cefalù.

The Cathedral and the Teatro Massimo are in different directions from the train station in Palermo. Both are within walking distance.

To the Teatro Massimo, it's a straight route that it would be difficult to get lost on.

For the Cathedral, I would suggest taking the somewhat longer route by Via Maqueda to Quattro Canti and then along Via Vittorio Emanuele rather than trying to find your way through the narrow and confusing streets of part of old Palermo -- unless you have an excellent street map of Palermo. In addition, taking Via Maqueda takes you by the Piazza Pretorio and its fountain (and I'd take a tiny detour through Piazza Bellini - continuation of Piazza Pretorio - to see La Martorana, a jewel of a church with lovely Byzantine-style mosaics.