Take an hour and visit your local bike shop that supports name brand bikes. We went to Wheel And Sprocket. These places have like minded people that have enjoyed the sport for many years and will know how to fit your wife onto a bike. Many times places like this take in bikes on trade and will have something in the back or at another location gently used and completely gone through at a discounted rate.
Good luck and let us know what she decided to go with.