It s tough to give an exact idea of how long it will take, both because commute varies depending on time, route, etc... and because Junipera Serra runs along 280 all the way through Daly City (so 280 and Junipero Serra isn t a definite point).That said, yes, morning traffic is very bad in San Francisco (particularly along major routes, which obviously you d be taking) and it will be pretty hellish. But manageable! During morning rush hour, I d give yourself around 45-50 minutes to get from the middle of SF to Daly City (may only take 40, if you re lucky).Japantown is a perfectly safe area... but if you re afraid of Daly City at night, I doubt you ll *feel* safe. It s next to a large development of housing projects and bordering the Fillmore, which can get seedy at night (I mean, there are restaurants and music venues, so it really is very safe... but the not to rare crazy and panhandler mixed in). But bordering Japantown to the north is Pacific Heights, which is very affluent, quiet, and *looks* safe (and is, but so are the other areas... they just don t look it) to an outsider. However, it s convenient to getting on 280.If you d feel more comfortable in a suburban-ish area that s still convenient to getting where you need to go (be it via 280 or Skyline), hotels suggestions would be Seal Rock Inn (Outer Richmond) and Oceanview Motel (Outer Sunset). For non-suburban but still very fluffy (though not quite as convenient, but not too bad), Laurel Inn (Laurel Heights) is great.
Japantown has a good and bad side, near Safeway s side is bad.. there s a bit of traffic in the morning, but it s ok.. You should have stay in SFO Airport, which is still close to 280. See if you can change it.