It depends on the doctor and the hospital whether or not you'll be cooperated with in delivering in the squatting position. It certainly is a good idea, as the pelvic outlet is 20-30% larger when mom is in the squatting position.
Also, women walk around up to 4 cm dilated for weeks sometimes so be aware of this just in case it takes a little longer than your doc is hoping it will.
If you wait for your body and baby to be ready, you have a better chance at a natural birth. Honestly, caregivers who practice the midwifery model of care tend to find that unless a woman was severely malnourished as a child or had an accident that affected the pelvis, babies just tend not to grow to big for moms to give birth to them. The plates in baby's skull overlap to help it fit, and mom's joints are relaxed from pregnancy hormones. Problems come up when labor is induced, when mom isn't moving around during labor or pushing in physiologically functional positions, etc.
There are squatting bars that can be attached to the hospital bed but you have to ask the L&D department and your doc what they normally do. If you don't like what they do, you have the option to choose your caregivers and place of birth over your birth preferences, fight for your birth preferences (often doesn't go well), or change caregivers; it's not too late. Freedom to move during labor is also very important for most women giving birth naturally as it reduces pain and helps the baby to get in the best positions for birth. This is especially important for bigger babies. Here's a video that shows all the maneuvers a baby has to complete in order to be born: http://www.youtube.com/watch?v=duPxBXN4qMg&NR=1&f... I think it illustrates well the idea that mobility during labor is crucial for some moms to get the baby in position for a successful vaginal birth.
Finally, and I can't stress this enough, GET A DOULA!!!! I would never attempt a natural birth in a hospital without one. If you cannot afford an experienced one, there are certifying doulas who will often charge reduced rates; just ask one of these doulas and they'll do all they can to find someone who is a good fit for you.
Here are some great local doulas: