I would say, quest + dungeon is the fastest, while queuing BG if the queue is fast when u tired or wanna kill some stuff, also, if its BG weekend, and the queue is fast, go for BG.
Other wise, i still prefer quest + dungeon. IM not a tank, so i will questing while queuing for dungeon.
One more suggestion, i have seen alot of new players trying to get party to do those group quest.
IMO, unless u wanna compete for achivement or you wanna experience the quest or the lore / story, else, u may just skip those group quest and move on. Save yourself some time and move on.
Also, always logging out in the inn to gain rest bonus,
Unless u are in a hurry, else, its ok to leave ur toon in the inn to gain rest bonus, go and play another character then come back to this toon and continue leveling, once rest bonus gone, then park it back again, and play on another toon with rest bonus. U can potentially save u alot of time by doing this.
Dont bother buying pd leveling guide
U can check out
http://wow-pro.com/where it house the jame leveling guide, u may opt for the manual guide, meaning u need to tab out and read it, tips: play in window mode, or u can opt to get wow-pro addons.
I heard jame is in the middle of reupdating some guides after cataclysm but then since u are level 61 now, there is no change to BC at all, u may follow his guide (Horde or Alliance, depends).
If u ask me whether its safe or not, then im cheating u if i said i can guarantee, i have used it before and there is no problem at all, thats all i can say.