If you're going to quest, you're pretty much stuck doing every quest. It's way too linear of a system to pick and choose easy quests. Questing works, but in some respects its pretty tedious. 80-82 shouldn't take you long, but after that it starts to take longer. Expect to spend about double, maybe triple of the amount of time it would take you to level a character 80-85 solo. I would steer clear of Vashjir and do Hyjal.
I know some people like grinding, but there's no way I could stomach it.
Another alternative you have is PvP. Which I guess is a longer, but maybe more enjoyable way to get to 85. AV weekend coming up this weekend. Might be worth a shot.