First, you go a nice deal by getting all that for $20. I would recomend that anything listed as an optional rule not be used when you first start out, especially if your group ends up being all or mostly new players. Once you get used to the basics, then you can start adding the optional stuff. You can also not worry to much about weight carried, food & water, and movement when you first start and slowly add these in as well.
To start, I would suggest using shorter games/campaigns. Ones that could be accomplished in say 8 game sessions or less (based on gaming twice a month). This way as you and the players get used to the mechanics of the game, you can add other extended/optional mechanics to the next game/campaign as opposed to trying to insert them into a current game.
Of course, don't be shy to ask questions on the forums here at P&PG. There should be plenty of folks that would be able to give you very good answers, no matter what game or edition/version you are using.
"You go 50 feet and come to a Y."