I've been considering starting up tabletop RPGing again after a 13-year pause. During the time I did RPGing before, I mainly used Advanced Dungeons & Dragons (second edition). In retrospect I think the AD&D system was far too clunky, with completely unnecessary rules and tables for all kinds of situations. I think it was a massive hindrance to storytelling, at least for me.
So this time round I'm looking for an RPG that is:
1) Story-focused. The adventurers should never be confined to a certain subset of allowed actions. They should be able to do whatever they wish and the rules need to be flexible enough to deal with that. The focus should be on a compelling story, not tactical combat, dungeon-crawling or levelling. However neither do I want a system that is pure storytelling - i.e. where absolutely everything is at the gamesmaster's discretion. I don't want to decide the outcome of every fight.
2) Suited to high fantasy. I'm planning on creating my own high fantasy setting, so it needs to be able to work with that (whether because it's completely flexible or because it's specifically focused on high fantasy). Guidance on how to deal with magic is a bonus.
3) Has rules which can be understood within an hour of reading the rulebook. I don't want to ever be scrambling through the rulebook to see what happens in such-and-such a situation, or trying to remember what special bonuses apply in a particular dice roll.
4) Isn't class-based. I want a system with complete flexibility about how the adventurers develop. Any system that requires they choose a class (e.g. mage, warrior, thief) is a no-no.
5) Ideally Free. Not because I'm in poverty, but because I think commercial systems have an inbuilt bias towards unnecessary rules, because it makes it easier to sell things (through expansions and new editions). This is the one criteria that isn't essential.
UPDATE: I'm going to go with FU, as it's got some gushing reviews, is ultra-lite and all the rules directly encourage narrative creativity and excitement. But keep the recommendations coming in as, if my first session goes well, I will investigate all other promising alternatives and consider how they might improve on the experience. Most of the systems recommended here are on my to-do list.