Trek Fuji Lemmond
size cm 47 48 45
top tube cm 49.3 50 49.8
stem mm -- 80 90
BB height cm 26.7 27.8 (not given)
standover in 28.0/71.1 28.7 72.5
crank length mm -- 165 165
wheel 650c 650c 700c
handlebar cm n/a 38 42
The Lemmond bike uses 700c wheels which are really too big for the frame. Watch out for toe clip overlap, and check that the long fork rake does not cause sluggish handling.
There is some variation in standover height, but as long as there is room, this is not critical. Generally, with a small bike you want a lower bottom bracket height, to aid mount and dismount. Use of shorter cranks will take care of cornering clearance.
All the frames have similar top tube, but the Lemond has a long stem.
The lemmond uses standard width 42cm handlebars. Fuji uses small sized ones.
The Lemond looks to be the worst in terms of geometry and proportions. Check the bar width and crank size for the Trek.
With these small bikes, they are generally proportioned so badly that its better to opt for the best proportions/fit, than go for the highest spec components or be swayed by some fancy frame material. Try for a test ride so your wife can check the handling characteristics and feel.