My daughter started in her "big girl" bed at18-19 months, it was the best thing I've ever done. Why do you think it necessary to keep her door open? Also, why wouldn't you shut her door? Is she not tall enough/able to open to door herself? If she is, that's what I would do? As a mother, you know what is and isn't acceptable to keep in her room, whether you are or aren't in there. I mean, this may sound bad to other moms, but I keep her door shut so she can't get out HAHA. I find it humorous in some ways -- but realistically, I dont want her jumping up and running out of bed/her room to the living room, our bedroom, whatever...
I would also def put toys in her room cause if she wakes up and you aren't awake yourself, she can play with her toys --- or what if she wakes up in the middle of the night, and is totally comfortable by herself, and just wants to play? I don't personally see anything wrong with my daughter waking up at 4 a.m. and deciding "hey! instead of waking up my mommy and daddy, im going to play with my toys like a big girl"
Have you thought about letting her pick out the bed herself? Our daughter is HUGE into tinker bell right now, and she just LOVES her Tinker Bell Canopy bed :) Its sweet. It also has detachable side rails for her.
I woudn't worry about her rolling around in the bed as some people have said you should put soft toys in there for her. I really don't understand that suggestion....i mean, she rolls around in her crib, and people have always made a big deal about PUTTING toys, specifically SOFT ones, in there in the event of suffocation or whatnot, am I correct? (I think so, not sure)
GOOD LUCK!!!!!