Cool. You've got me thinking of other options for our bike, too. The trick might be as simple as finding really skinny 26" tires. Although since our boys will outgrow the bikes, correct resto might give the best resale eventually.
I cut my teeth tinkering on my parents' '70's Atalas as I grew into them, but I recommend '80s japanese bikes for learning to wrench. Parts are cheap, plentiful, interchangeable, and easy to work with (no cottered cranksets).
__________________
The bicycle, the bicycle surely, should always be the vehicle of novelists and poets. Christopher Morley