Red Flag means that teams can work on the cars. Safety cars they will not be able to.
Think of it like this: The last lap before the safety car comes into the pits is like the warm up lap at the beginning of the race. At the end of that lap, the cars will line up on the grid. Once all cars are on the grid, roughly 10 or so seconds later, the race will begin or the race will restart.
It looks to me like Massa got alongside of Perez, and Perez thought he was clear, and turned down, but Massa had the momentum, and slammed into Perez. Happens all the time in other major forms of motorsports.
And besides, a driver should be able to drive in a straight line down a straight without another driver cutting them straight off and wrecking themselves.
This race has had some freakin awesome racing so far. Usually on an average Grand Prix I sit on the couch, watch 10 laps, then move to my laptop and occasionally move back to my couch if something happens. I've been sitting on the couch this entire race. Only touching my laptop now because of this safety car break.
You should be able to bring every drink in the world in besides alcohol!
Unless the rules are different from there to hear, you will not be able to take beer in to the track, or out of the track at the end of the day. Beer is available there at the track though, of course!
I recommend you pack water to drink throughout the day, though. Also bring sunscreen, you don't want to forget that, especially here in Australia!