Hello Soulsearcherr,

*I am assuming you are doing a traditional wedding that takes place in a church or hall? *

Using a higher ASA / ISO is recomended for darker settings, the higher the ASA/ISO the more light sensitive the film is, therefore allowing for a faster shutter speed, but with more grain.  I would personally recommend using a flash and bounce it whenever possible, remember bounced light is always more flattering then light flashed directly.  A diffuser for that flash is also a wise investment in case you have to flash directly, meaning bouncing the flash is not possible due to a either a dark or catherderal ceiling.

I would also visit the place where the wedding is to take place and do some test shooting recording each shot ASA/ISO, shutterspeed and aperature, this way you know what works and what doesn't, if possible take a friend with you to use as a model.  It is not dark here at 7:30 is it dark there?  Are you worried because the wedding is outside?

I personally like using my DSLR, this way as the wedding is progressing I can see that the images are coming out, and it helps me to relax a bit knowing this, digital is also easier for me to postwork, and I can also provide images in sepia and black and white.  When shooting film and being nervous there is always the possiblitiy that you may forget to load the camera or set a setting and you won't know how they came out until they are developed.

Another little pointer, dress nice but comfortably, this way no matter what position you are in you aren't fussing with your clothes

Sometimes it also helps to work with another photographer your first few times, this way the bride isn't relying solely on your images.

I hope everything turns out for you.  Keep me posted.

The Cynical One

I have forced myself to contradict myself in order to avoid conforming to my own taste.  -Marcel Duchamp