Chelle, you asked about receiving gifts. If the people you're gifting aren't sending gifts back to you, they either aren't neighbors yet (you can send "pending" neighbors a gift but they can't reciprocate until they accept the neighbor request) or they're not actively playing Farm Town. You can either message your neighbors and tell them you'd really like to have some mango trees (or whatever) as gifts ... or you can get some more neighbors who are active. Or both. Check out the "Official" Facebook neighbor request thread at the top of the social section of the forum to find people who want more neighbors; just the last few pages should give you all you need, and those are the most recent ones.
There's nothing you need to "activate" in order to receive gifts, except maybe giving your neighbors a nudge if you're comfortable doing that.
Happy farming!