These days it takes a lot of $ to get above the garbage sold by mass merchandisers. I used to look for used bikes at garage sales for kids in my Scout troop who were going to attempt cycling merit badge. I wouldn't give a second look at a bike that had a solid rear axle or limited gear range. It's the lowest of the low when the manufacturer uses that kind of component so I would cross the first bike off your list. Lighter is always better. The other thing you might do is to get the weight of the bike if the store where your wife works has that informationt. The alternative is to carry a bathroom scale into the store and weigh yourself and repeat with you holding the bike as steady as possible. All three bikes have entry level front suspensions, As has been mentioned, they add weight, likely offer little real effect on the ride, and are just one more thing to go wrong, I have an old Cannondale SM800 MTB that I bought used dirt cheap years ago. I'd put it up against any of the bikes you list when it comes to weight (26#) and durability. No front shocks, just a quality frame and good components. Make sure you get the right frame size. If the bike comes in "one size fits all" or isn't available in a frame that fits you, skip it,