You need at least Organic filters, but I'd recommend Organic + Particulate.
The cartridges need to be made by the same manufacturer of your mask or be compatible with it. Be sure you know how to do a fit test to make sure you've got a good seal, and don't over-tighten the straps.
Masks come in Half and Full face mask varieties. I'd go with a full if you're planning on doing more than just the fiberglassing. Otherwise, safety glasses/goggles should be adequate to protecting your eyes.
Also, if you wear contacts, don't wear 'em while working with particulates. You can get safety glasses that fit over prescription glasses, and you can also get safety-styled sets of prescription glasses from your optometrist.