The bus service is alright, although the double-decker buses sway alarmingly going around corners. The number 1 takes you straight into Lancaster. Any number 2 bus will get you there as well, by a rather more round-about route. If you can, go with a friend, as this makes the trip more enjoyable. That's the peacock.
Porters have a great many functions.
Basically, if you have a question, a porter is a good bet. Each college has one, and they are there 24 hours a day, theoretically. In practice, the porters lodges may sometimes be empty. Your mail pigeonhole will be in the porter's lodge. Be sure to ask where it is.