It's not possible to give you exact information as the exposures you will use will depend on your night skies -- light pollution, haze, scattered light from the Moon, etc.
An ISO 100 film will do the job. Very grainy films do not give satisfactory images. Color slide film is best as there is no loss of contrast/sharpness in a printing process. Set lens at infinity and use one stop down from your widest aperture. Then try a range of time exposures. You will find, when you examine the results, that stars have different colors. Your first roll of film, if you take notes of the exposures, will tell you lots of things. Exposure is a trade-off. If you stop down, you can expose for a longer period of time before the background sky light will fog the image. This will provide longer star trails, but you'll lose the fainter stars. The choice of focal length, aperture and exposure time depends on just what sort of an image you're after.
Learn your sky. Free download-able star maps are available from several sites. The 2.7 Meg Basic Program from this site will get the dog walked, and then some:
http://www.stargazing.net/astropc/download.html
Pick out stars of various magnitudes [1 through 4] as references. Some nights, all you can see are mag 2 and brighter. Other nights, mag 3 and brighter, etc. By knowing the magnitudes of a few reference stars, you can accurately judge the photo conditions. There's a nice series to be found in Ursa Minor and the stars are visible at all times of the year. For brighter stars, either Ursa Major or Cassiopeia are visible each night. Right now, Cygnus and Lyra are overhead in the early evening. All five are easily-recognizable constellations.
Try including an Iridium satellite flash in a photo. They can be very bright -- up to mag -8. There are other satellites visible almost every night with various magnitudes. Here's a site with information on them -- just log onto it and enter your longitude and latitude. It will provide nightly predictions. [It's a freebee, too!]
http://heavens-above.com/
As a side note to anyone reading this: catching an Iridium flare or seeing the space station or shuttle is worth the effort, IMHO. About all you need is your longitude and latitude, a decent view of the night sky, a timepiece and the above site. The nature of satellite viewing is such that you don't even have to stay up late. Binoculars of not more than 7X are a nice aid.
