You're running instances at the levels of the characters you're boosting.

So if your druids are currently lvl 10 you would take them to Deadmines and boost till 15. At 15 you head over to Stockades, etc (this is if you're Alliance). The problem you'll run into with an 82 shaman boosting is when you hit Lich King instances your shaman will have difficulties or not be able to solo the instances.

You have 90 days of RAF so how you go about leveling your teams will depend on how many teams you plan on leveling. If you only want a Druid x 3 team then you have plenty of time to quest to 80 and speed won't be an issue for you.

Gifting of levels will depend on how you linked your accounts. For each character leveled 1 to 80 on a recruit account you'll have 39 levels to give to the veteran account.