Travel tips for Southern Italy and Sicily...Possibly getting married there also?

My boyfriend and I are planning a trip to Southern Italy (Rome, Naples, Capri, Palermo etc) including Sicily in March or April of 2008. We have never been to Italy and we plan to go for 10 day (not including the travel days to and from). We know that we need to do a tour or we would never see the things we want to see but we don't want to be restricted to eating with the people on the tour and staying in the hotels they stay in. Basically, I would like to know if anyone has taken a trip to Italy where you basically set up the sightseeing tours only, you can eat where you want and stay where you want but they set up transportation to and tours of sight of interest. We want to stay at the nicest places and have freedom to eat where you want, are there any companies that allow you to do this. We are also thinking of getting married in Sicily, he has some family there (whom he has never met, but are very receptive to our coming). We would basically be eloping(just the 2 of us, no one knows) we want a Catholic ceremony then when we come home we would have a nice Civil Ceremony for just close family and friends (he works for a judge so he would perform the wedding). Is this possible and if anyone has done this please let me know. We would also like to start off in Sicily b/c that is where my bf wants to get married and then the rest of the trip will be our honeymoon, is this possible. Any info will be appreciated, especially from those who have traveled southern Italy and/or American citizens who have had a Catholic wedding there.
Additional Details
Thanks for the advice Pearl, but I am Catholic hence, the reason I wanted a catholic ceremony, and have made my sacriments (baptism and confirmation)