I, too, went to see this movie (alone), and I, too, was sooo excited to see it but ultimately disappointed by a lot.
The first part dramatically and brilliantly set up the audience to see just how bad earth was - the utter lack of life in the US was horrible for me. But that kind of painful reality is what really drew me in to the movie itself. I was beginning to identify with the perspective of the moviemakers, and I thought that maybe the movie would have some really useful and honest commentary on all that. And the potential for despair at the lone machine left running, Wall-E, handling everyone's garbage alone, forever, was profound.
I have some criticisms, however:
The love story really turned me off. I was also disappointed that the robots had to be gendered for people to like them/not feel disturbed by their "relationship". And in fact, as the movie progressed and it became obvious that it was actually a love story, I hated that direction.
And the human portrayals and characters were full of problems related to believability in plot and character. And the animals - how could they plant in the soil? So many plot flaws it made me crazy.
But my biggest disappointment was at the very end of the film, during the credits, when we see the humans rebuilding "civilization". For me, that was the worst. By rebuilding, they were all set up to reproduce the same values and culture that started civilization on the path to the craziness we're in now - the culture and lifestyles which created the heavily polluted, unlivable earth by killing the wild earth itself and the wild humans in themselves (a bit of a metaphor).
I loved how a little bit of earth, represented by Wall-E, was able to disrupt the perfect, mechanized predictability of the Axion. However, I think there is also another message piggy-backing on all of that, that of technology saving us from ourselves and the killing of the planet. This is a lie, but we all kind of believe it. Or rather, we love movies that make us think that maybe it's true. But it isn't, and super-cool robots and technology will not save the earth or the animals or us.
Mostly, I think the glorification of heterosexual romance and love is the main reason I won't recommend it for my girls. For me, this theme is rampant in Disney movies (and other kid-friendly movies) and not the real thing that changes the world - yes, we need to love each other, no matter the gender of our romantic partners - but why on earth does hetero romance need any more miracles pinned to it? It's just over the top for me.
Real change is needed on our earth right now, but robots falling in love will not save us from dying on a dead planet. I guess this is such a serious topic for me I can't stomach having it watered down to what this movie does, and then have so many people who have seen it feel like it's a strong environmental message movie.
But the robot animation and all the images from earth were spectacular. Just amazing.
I would definitely check this out from the library when it is available on dvd.