[pliny]

Cormen & Rivest's Introduction to Algorithms is a solid and decently paced book that covers a lot of what you would realistically need to know to start working in CS, as far as theoretical knowledge is concerned, and will give you the tools to understand the merits of new algorithms and data structures as you encounter them.

After that you should try to get through Ullman's Introduction to Automata Theory, the dragon book and Sipser's Introduction to Computation Theory.

Those are the 'core' elements of a CS education, although it misses everything to do with how your computer and OS actually works, but I don't know what to recommend for those.