New bed and new room are 2 BIG changes for a child who just turned 2. They thrive on routine and predictabilty at that age. Why do you want her out of the crib? It's pretty common to have kids sleep in cribs until closer to age 3. If she's not climbing out, sleeps very well and likes her crib just leave her be. Don't fix what ain't broken! I know you want a crib for the baby, but think about it.... will the baby be in the crib from day one? If he/she will be in a bassinet then you'll have a few extra months. Or do what we did... buy a 2nd crib for that transition time (our 2nd child turned 2 just 2 weeks before #3 was born). We spent like $75 for the crib and mattress by buying them from another mom in my mother's group. It looked brand new and was only a couple years ago so it was up-to-date with the safety stuff. The crib was only used for a couple months, because when the baby was 5-6 months old (she slept in a bassinet the first 2-3 months) our older daughter was ready for a big girl bed. We then sold the 2nd crib (still in excellent condition) for $75 and made our money back.
If you still decide to use the current crib for the new baby, just move the crib in for now. You still have a few months until the baby needs it. Let her sleep in the crib in her new room for a few weeks or a month until she's used to the room. Leave the twin bed in there so she can sleep on it if she wants. After a month or so, talk it up for a few days and then take out the crib. Changing one thing at a time is much better for her.
We moved our older daughter to her new room about halfway through the pregnancy but she had her crib. She was still a bit hesitant the first night, but she loved being in her crib so she was fine. It did take her a little extra time to settle down and fall asleep, though.