Lee, O'Saughnessy, Johnson, Pritchard, Miles, and Slusher are some of the most common freshman dorms, and are all located relatively near to one another, and they are all pretty similar (hall style, common bathrooms, etc.)
To my knowledge, you get to choose whether you want a bunk bed, lofted bed, or just separate beds when you get there. I think that all of the beds can be converted to whichever style you want to have.
Hope this helps, and I'm excited to be a Hokie next year as well! Class of 2016