I've actually stayed at the property that you're staying at. Rooms are a bit small but clean, nice location and nice shopping around. When we took the train in, the bus driver only had three people on the wharf and he dropped us off across the street from our hotels.
As for crime, SF is really a pretty safe city for the most part. Basic disclaimer is to keep good track of wallets, purses, don't flash cash, and know that there is a homeless population around in places. But the city police are effective, mass transit is prompt and relatively clean, and I've never had any real issues other than occasional bursts of pan handling. Again, just maintain situational awareness and you'll be fine. There tends to be a lot of tourist traffic at night, especially on weekends.
From where you'll be, there's a major tourist attraction nearby, Pier39, with a nice assortment of stores, dining, and the like. Moving towards the golden gate bridge, there's a state maritime museum that has several really neat older ships including a Northern Pacific car ferry. In your immediate neighborhood, there's a Trader Joe's and a Safeway, a book store, and other shops. Another fun trip is to ride the ferry over to Sausilito and enjoy their waterfront. There are some really neat art shops and the like over there, plus crossing the bay can be fun.
Other outings worth pursuing would be Alcatraz (book early, that tends to sell out quick in tourist season), Angel Island (an old TB asylum / immigrant way station now turned into picnic areas and walking trails), and Golden Gate Park.
Probably gave you way more info than you asked for, but hey, it's my favorite city. Enjoy your trip and have a blast!
Mike