I'd echo anydream... with the 'meet from school with a snack' line. It doesn't have to be a sugary, 'bad' snack - I give mine a little box of raisins, a banana (and NEVER a finger of Fudge or a small brownie) and a carton of fruit juice.
My twins were aged 4 and 3 weeks when they started Reception and the first couple of terms, the days I forgot the snack they were very whiny and short-tempered in the next few hours at home after school.
It's a big transition for them of course but mine fell into the school routine REALLY quickly - I think it made them feel grown up (we had been reading a book called Puddle's Big Day for weeks before, about a duckling who wanted to go to school like all his older friends....) having their own bag and learning new things etc...
Mine went full time from the off - 8.45 am to 3.15 pm and I didn't have a single day of leg-clinging or crying that they didn't want to go. I do admit though, that having each other there will have been a huge comfort (we are splitting them up into separate classes when they go back next week in Year 1).
Prior to starting school they had done three days at pre-school (9 to 3) so they had some idea of the structure.
Could you maybe do the first couple of weeks part-time (picking up at lunchtime or something?) and see how your DD copes? You may well find that the stimulation and excitement sees her through and she sleeps like an angel for you every night!
We can hope eh? Good luck!