Have you read Confessions of an Organized Homemaker? Check you library for it.. it's a GREAT read! It's not very long but has wonderful and simple ideas about decluttering, organizing, and simplifying your life.
We also ask for more practical things like the things kewb said. Then they really know DD is USING it!!! As for the plastic junk, my husbands family is gigantor in size and mostly all give the boys gifts. It still gets ridiculous, but over time the big spenders (his parents) realized we just give away the crappy toys, so they started buying nice ones, and usually will actually ask what they want. I fell no connection to the junk that people give us. When the kids are younger, I actually pre-open their christmas and birthday presents and discard of the crappy ones - still works for my 2yo.
For my 5yo we have a different strategy. If there's a toy he's really in love with and it meets our already designated family toy guidelines (no annoying noises, no guns, no characters), but it's still a junky toy, he can play with it until it breaks, and then it gets given away. He's rough on toys, so we especially let him take the junky ones outside and roll them in the mud, bury them, rock play, etc. (oops! did it stay out in the rain?

), until it's broken. I've also found it's lessened up as he gets older, because he can actually ask for what he wants - so most people aren't just giving him whatever crap they find at Walmart or Dollar General.
So for your 2yo, just toss the junk and don't look back. If anyone asks, tell them the TRUTH - There were getting to be so many toys from your sweet, generous relatives, that she was overwhelmed and couldn't really enjoy each one, so you needed to declutter. I promise every single parent in America can relate to that!
As for birthday parties - we just have potlucks. We write "In leiu of a gift, please bring a dish to share!" It goes over well, and still actually most people bring gifts, but very few are the walmart (spent too much money on junk) type. Most are like some stickers, neat box of bandaids or something little. We have told DS (5yo) that it doesn't matter if people bring gifts or not - that's not why we want them to come to our birthday parties, ya know? (I also told him that some of our friends might not have the money right then to buy a nice present and feel like they can't come to the party - so we don't want people to "have" to bring presents - which isn't really true, but I think that comment put him in a better frame of mind

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