L.R.
I would go for a twin bed if your crib isn't a convertible one. Another mom had a great idea about putting the pool noddles under the fitted sheet on each side instead of buying safety rails which I thought was a great idea and even saw a similar thing in the One Step Ahead catalog yesterday! Of course you will be dealing with how to keep her in a regular bed at night once you make that transition so be prepared. Our pediatrician told us to wait as long as possible, even if that means buying a crib tent, before moving our daughter into a regular bed as toddlers have a hard time understanding the imaginary boundaries. My daughter is 3 and still LOVES her crib so we haven't had to face this issue yet.
Sincerely,
L.