Hmm. I don't really know. I tend to be a pretty all or nothing person (shocker right?) so the day I decided I wanted to learn to cook, I bought books like The French Laundry cookbook and the Culinary Institute of America's textbook. I'd tell someone who really wants to learn to cook to use rice makers for making rice.
If someone was really interested in learning to cook, I'd tell them to get Ruhlman's 20 and Ad Hoc at Home. Both are relatively approachable and explain technique rather than just list off ingredients and instructions. Then work your way up the Thomas Keller chain (Bouchon, then TFL) because not only is he on everyone's short list for best chef in the world, but he puts a huge amount of effort into the books, even down to the typography, which a lot of other great chefs don't. (John Besh's book is great too btw.) He really goes out of his way to explain why he does the things he does.
Ruhlman's Twenty is a great first cooking book. Heartily seconded. I'd get "Ratio", and the Kindle version of "The Flavor Bible", to accompany it. That'll set you up for a lifetime of cooking without ever looking up a recipe again.
(Keller's books are all Ruhlman's writing, right?)
I don't really like Ad Hoc at Home. It's IMHO unnecessary in terms of techniques and complexity. I don't need to blanch my vegetables to make dinner for my family. Admittedly I wasn't wowed by my meal at Per Se either. I would like to go to TFL though.
I do worship Rulhman though. I also recommend Jennifer McLagan's books for working with nose to tail basics like stock and animal fats.
I usually recommend people visit really good restaurants and seek out books by their favorite chefs. That really got me into Asian cooking through being a fan of the Momofuku restaurants.
If someone was really interested in learning to cook, I'd tell them to get Ruhlman's 20 and Ad Hoc at Home. Both are relatively approachable and explain technique rather than just list off ingredients and instructions. Then work your way up the Thomas Keller chain (Bouchon, then TFL) because not only is he on everyone's short list for best chef in the world, but he puts a huge amount of effort into the books, even down to the typography, which a lot of other great chefs don't. (John Besh's book is great too btw.) He really goes out of his way to explain why he does the things he does.