In my ongoing quest for a commuter bike that I would feel happy to leave chained up outside the office, I had a wave of inspiration while visiting my parents at the weekend. They are in the slow process of planning to build a new house, and will need to have a massive clear out in the process. Their garage contains my bikes of yesteryear, and I was wondering if I could modernise one of these to make a reliable commuter. There is a choice between an early '80s Raleigh (my 14th birthday present.... how could she have been 14 in the early '80s, I hear you ask.... ) or my student bike... a bit of a frankenbike, build around a frame that my father found in the garage when they bought the house (so early '70s, possibly older). There also was another random steel frame (think from an old road bike that dad bought from a colleague).
Either way, I am thinking that I would want modern gears / brakes / components.
How difficult/expensive would this be to do? Is it too complicated for someone of my mechanical expertise?
If feasible, how do I decide which one to start from?
Would it actually just be best to buy a cheap road/CX bike?
... and no one suggest a fixie please!
Any top tips gratefully received!