Ideas needed for novice rider

For her I suggest a Felt SR-81 47cm with 650c wheels, it had flat bars and a more upright position.
http://www.feltbicycles.com/felt2006/05SPEED/sr91.php

Andrepaul said:

I'm a cycling fanatic and have all the lightweight equipment and really enjoy cycling (I can't get enough of it). My fiance, on the other hand, sometimes enjoys cycling with me but is a bit turned off by cycling because she rides a heavy tank of a bike (Trek Navigator 100). She prefers to ride with me on paved paths for 5 to 10 miles and likes the upright stance of a mountain bike. Is there something that we can buy her for maybe $500 in aluminum that's lightweight, fun to ride and good looking that's not a road racing style of bike that will fit her correctly (she's 5'1"😉? I'm thinking that we could get her some kind of small, upright, Al frame with straight bars with very thin road wheels and tires. Any suggestions? I'm all for building a bike from components if needed.
Thanks

One option for a couple who are disparite in size and strength is to get a tandem bike.