There are several winners in the 250 category. Each have their own cult following. If you go with a Yamaha xt250 you get fuel injection (2013 and later). Max speed about 75mph. Can do short interstate work if needed. I'm unsure about other brands and models. Its seat height is lower, which could prove helpful for teaching the wife to ride (not sure how tall she is). FI is important for elevation changes so you aren't fiddling with a carb.

If you were to go with a used TW200, which has a max speed of about 60mph, I would recommend going with a model from the earlier to mid 90's. Those models still have a kickstarter in addition to electric start. Don't go with an '87 as their CDIs are notoriously finicky (there is an after market which addresses that -- developed by one of the guys on tw200forum.com). Other than the electronics, very little of importance has changed on the TW. The TW has a carb.

You could always buy two used. Once the summer riding season tapers off, more bikes will become available for sale. Can then do any refurb over the winter and voila, come spring you and the wife are riding.

I know there are going to be folks who swear you should get a KLR5000 that you need a crane to get on and the back tire can kick rocks into Kansas. That's cool for those guys. I really enjoy the mule-like aspect of the smaller bikes. YMMV.

If you find yourself back in the Springs anytime soon, I'd be happy to let you test ride the TW. If you get a chance, have a seat on an xt250 as well.