I had just recently come back from an eight day vacation in seattle and when I tried to drive somewhere my car wouldn't move. It would crank fine, but it wouldn't move. The check engine light even came on. After I floored the gas, the car finally moved but made a large bang noise. Now the car is fine but a friend of mine told me that if you go on vacation for longer then like a week or so it won't start and the car will have to be jumped off. Ive tried googling information about this but I haven't found anything. I was just wondering if this information is true and what do I need to do to stop it next time I go on vacation (which will be soon)?

This may seem like a wild guess but I believe your disc brake surfaces rusted a bit during the past week. The calipers partially seize the disc and then pop once when the car is moved. Disc will always rust to a certain extent if not used regualrly, its OK. Not a jump the battery issue at all.

A car will start after a period, if all else is fine... Our car wouldn't start one morning, she would turn over and rev if you gave it some throttle, turned out we needed a new battery! There just wasn't quite enough in it to keep her running! Think of a torch with a dying battery, when you wack it, it goes for a bit longer :)
I don't claim fame to any great knowledge... what I write is only from my experiences!!

I understand but this person's car started, it just would not move forward. "would crank fine, but it wouldnt move" The brakes were likely seized and broke loose when enough throttle was applied

Yeah... sounds like you know what your talking about ballengerb1... I answered this before I saw your post... but will it happen again? How do you prevent it?

There really isn't a great solution to this problem because even humid air is enough to start rust let alone rain. You can't spray anythong on the disc without endangering your brakes. A disc brak is abig piece or bare steel without an once of rust inhibitor. Try to keep the car indoors for long storeage if at all possible. It really isn't a big problem because after the first popping noise the brake is fine. Once you put your foot on the brake pedal the pads rub away all of the rust.

That's interesting about the brake thing. I don't know much about cars and when my friend told me that the battery would die if I go on vacation for a long period, I had to ask. Thanks for the info, hopefully my car won't have to be jumped off when I come back.

Did you apply a hand brake? As said above the brakes pads probably rusted to the disc, a hand brake keeps direct contact between the disk and calipers, if you can store it indoors don't apply the brakes and use chocks instead.

Yes, leave the e-brake off. I find that this is not an issue with our cars with factory pads, but if it has the so called guaranteed forever parts store brake pads on it, this happens.
I see cars on the lot sitting in the same spot for a month or more. No problem. But the battery must be healthy. Many things like clock, radio, computers, need to suck a little juice all the time while off to keep their memory.