Aren't you like 16 or something? A little young to be thinking of a credit card. There are a few reasons for that. If you are under 18, you will need a car with a cosigner. That means that a parent or older relative will be responsible for your card if you don't pay it. I think these limit how well your credit will build, even if you pay it meticulously. Also you don't really have a need for one under 18.
As for the starwood preferred guests cards....First of all, they are american express I am pretty sure. This means that you will not only be paying a yearly/monthly fee to be a Starwood member, you will also be paying a fee to use this 'premium' credit card (AmEx) that has higher interest rates, higher caps, etc. My family is part of Starwood, these cards are pretty nice. This is how they work, for every dollar you spend, you get one StarPoint. You can spend StarPoints to get nights at hotels. One night at a decent hotel will cost you about 4000-10000 star points, or the equivalent of 4000-10000 dollars if you were to pay it straight up. It isn't REALLY that much, because you are essentially getting a free room for however long you want to stay there, but you need to spend alot of money to be eligible for that. The only real advantage to the starwood cards is if you are a timeshare owner, and you can also get a free room upgrade if you are paying for a hotel because you are a "preferred guest"
All in all, you will be spending alot of money for two reasons with that. One is because its a starwood card, and two because its an American Express, at least my parents are. Your BEST bet is to wait until you are 18 and find a card that does not need a cosigner. These cards will have no rewards or things like that, but that is ok. Cards that sound almost too good to be true with all the awesome rewards they give are just that...too good to be true. You will be paying for it in the long run. So like I said, wait till you are 18, get a visa or a mastercard that has a low limit, no monthly/yearly fees and no cosigner. That will be the best way to build good credit provided you pay your bill ontime.
*phew* that was alot of text.