Spending 5 nites in early May in S.F. and have the choice of the Alamo Sq. Inn (at first I thought it was in Pacific Hts, now realize it's really in Western Addition), or at the Nob Hill Hotel on Hyde St., about 6 blks from Union Square. Which is safer nitetime neighborhood? Any opinions on either inn? Many thanks for help asap!

My wife & I stayed three nights in San Fran last November in a lovely small hotel called the Juliana in the Nob Hill area. This area borders onto Union Square and, although the roads are a bit steep, its close proximity to Union Square, Chinatown & the Trolley line down to Fishermans Wharf, made it a great place to stay.
The reservation was made online through San Francisco Hotel Reservations, whose site I found extremely user friendly and whose prices were very competitive.
Don't forget Alcatraz - it was great - but try to book BEFORE you leave !!

Lois- if the Alamo Sq Inn is in Western Addition, it really isn't the best place to be staying. It's not one of the safest neighborhoods in the City. The Nob Hill at Hyde doesn't sound much better b/c based on your description, it sounds as if it's right on the borderline, if not in, The Tenderloin, a seedy part of town.

Antony makes a good suggestion for the Hotel Juliana. I work about five blocks from the hotel. It's very close to Chinatown, Nob Hill, and Union Square. You can also catch the cable cars (not to be confused w/ trolleys - those electric streetcars) close by.

In all the tour guides, one is advised to avoid this neighborhood at night and/or althogether.

Please take the other posters' advice and look elsewhere. There have been several good posts recently on budget hotels in San Francisco. I can personally recommend the Cow Hollow Motor Inn on Lombard Street. It is clean, reasonably priced, and located in a safe neighborhood.