My younger two love Tangled. They did have sone questions when watching it, and had bad reactions to bits of it, but overall they thought it was brilliant. Especially the horse 
DD muttered about wanting (like Rapunzel) to escape from me, "Well THIS house is a PRISON because of YOU"
DS, on the other hand, talked about being kidnapped afterwards...he asked what would happen if he was kidnapped away from me by an evil witch. Clearly he percieves me not as the evil kidnapper, but as like Rapunzel's mum the Queen :) I told him that that would never ever happen, he said if it did would I keep looking for him like the Queen looked for Rapunzel, I said I would look even harder. Bless him
Italian - yes, I think most children pull the "you aren't my mum", "I'm going to live with grandma, I hate you". Adopted children get to pull the "you aren't my REAL mum" and "I'm going to live with my real mum, I love her more than you". Ouch. But I think you just have to remember that it's the same as other children wanting to live with grandma - they don't actually mean it, but they've worked out that it's a hurtful way to show how angry they are with you. Not to be taken personally, even though I do think adoptive mums are more likely to take it personally (me included at times)