Following along in the same vein as my "Entry Level Upgrades Topic", http://www.cyclingforums.com/t363004.html, I propose to buy and upgrade a new model Huffy Blackwater as soon as it is released in 1-2 weeks by K-Mart. The 24" bike will suit the shorter rider.
See: http://www.huffybikes.com/bikes/index.html Mountain Bikes 10 and up, the bike is the Blackwater Boys/Mens 24" frame.
Options I will look at are:
Wheel size: 24", 26" or 650c
Tyre size: 1.5", 1.25", 23mm slicks
Crank length: 140, 152, 160, 170, 175mm
Brake callipers: Choosing the drop, 60, 75, 100mm, to suit the rim diameter.
Chainrings: 28/38/48 (should already be standard)
Freewheel Cassette: 6 or 7 speed, 11, 13 or 14 tooth top gear.
Shifters, 6/7/8 speed, Thumb, Twist or Rapid Fire.
Chain: Full index type, 7/8 speed
So, stand by for a fun low cost project. 😄