>>3356479The cheapest film you can find in your area. As a beginner it's best to stick with things like Colorplus, C200, maybe Xtra 400. For B&W try Kentmere or Rollei RPX series. Leave expensive stocks like Portra, Ektar and slide films for when you have an idea what you're doing. Since you have a zoom lens, make notes which focal lengths you tend to use the most and get prime lenses that match those. Series 1 is as good as Vivitar gets (if it isn't later batches where they just screwed people off and ruined their brand) but old zooms tend to leave a lot to be desired.
The MD1 adds a handle that helps when using big lenses but it also adds significant bulk to the camera (because you stuff it full of batteries). Honestly you won't need it for much unless you shoot sports and wildlife. It is also very loud. I usually leave it out unless I'm shooting with a tele or a heavy zoom.
