I think some of the questions you're asking have already been answered earlier in this thread, so you might want to start by rereading some of the advice you've already been given. You probably should also take a look at several articles in the planning section of this website, especially the international visitors topic.

$60-70 is a pretty average price for a budget to midrange room, but that's going to vary quite a bit based on other factors like location and time. If you are looking for a room on the vegas strip or a on the California Coast, you could be paying much more. Reservations are a personal preference as much as anything else. You don't always need to have them, but if you've got a preference to stay at a specific place and since you need multiple rooms, it wouldn't hurt to make them in advance. If you think your trip could be changing, find out what the cancellation policy is.

A contiental breakfast generally means coffee and juice with donuts/bread/rolls. There can really be a pretty big spread on what this means, but generally, the nicer the motel, the nicer the options.

ATMs are available at banks, gas stations, grocery stores, etc. They are very easy to come by, although bank ATM will usually have the lowest fees.

FastPasses at Disney are free and available at most of the more popular rides.