If you find the complexity of some RPGs overwhelming but still want solid crunchy rules to govern your alternate reality, this is worth a look. It's basically a cut-down and simplified version of the D20 ruleset pioneered by Dungeons & Dragons 3e.
The real appeal of this, however, is that it's designed to be easy to explain - as in, once you have absorbed the rules herein, you ought to be able to explain them clearly to someone else. They're not particularly easy to read, or at least, not any easier than any D20 ruleset is; and it certainly will help if you understand the core concepts of role-playing in general and the D20 ruleset in particular - yet once you have read through these rules you will find that the underlying simplicity becomes clear and it will be easy to sit and explain these rules to a group of novice players.
Everything you'll need to set up the characters comes in the first 11 pages. Characters have three ability scores, rather than the six veteran D20 players are used to, and skills are drastically reduced. The core character classes are all there, albeit in simplified form. There's still a goodly list of equipment, weapons and armour, though.
Next comes the GM section which is basically a speedy run-through in three pages flat of various perils the characters might face, putting numbers to their effects. Poisons, illness, traps, things like that. Oh, and how to work out treasures and other rewards.
Then magic gets a similar cut-down treatment. Most spells - and there's a wealth of them nevertheless! - are reduced to a couple of lines summarising their effect when cast, and that's it. So 'Read Magic' for example allows you to 'Read scrolls and spellbooks' - that's it. This is followed by a basic monster list.
Finally, there's some basic materials to let you create random adventures with a set of charts to roll on for location, protagonist, antagonist, objective of the adventure, fluff elements and a reward for completion. There's a basic outline map of a continent and tables for you to detail the names and natures of the countries you want to have there. Oh, and there's a good clear character sheet template.
You want a basic, quick game, this is for you. If, as an experienced gamer, you want to introduce novices to the hobby, it should work well provided you are a reasonable explainer (I'd feel quite confident, but I am a teacher...). Neat with touches of elegance.