Oh, sorry, I see you answered that in the title. Duh, my fail.

The latest edition of Warhammer Fantasy Roleplay is actually quite good and readily adaptible to a range of settings.

Gurps? Generic Universal Role-Playing System.

For simple, I really think you cannot go wrong with Wushu-Reloaded.
The rules are free, and the game is generally speaking lite and lends itself well to encouraging the players to have a blast with it. I highly recommend taking a look through the example gameplay section of the rules.

Gurps is fun but takes too long to create a character and learn the in's and out's if you've never played before.

I have played GURPS, Vampire the Masquerade, AD&D, AD&D 2e, D&D 3.0 and 3.5, Star Wars Revised Ed., Star Wars Saga Ed, Shadow Run, Mech Warrior and a few others that I can't think of right now.

Dice Usage: (ordered from least to most):

Star Wars Saga Edition
GURPS
D&D (no wizards in your party)
Vampire
D&D (wizards in your party)

I have the longest standings playing D&D and Star Wars. The fun-factor and ease of rules of the d20 system cannot be under-stated. Players and GM's alike can pick up the books, read through it once, and learn the system really quickly. The biggest drawback to D&D is that there are tons of sourcebooks which can mean $$$ if you wanna keep up. Plus, every few years they change editions. The benefit, though, is if you decide to go with a slightly older edition (like D&D 3.5 or Star Wars Saga Ed. instead of D&D 4.0 and SW Edge of the Empire) you can find all or nearly all of the sourcebooks online as PDFs as well as tons of premade adventures.

Vampire and GURPS have very loose rules giving GM's more flexibility, but going from one GM to another can look incredibly different and have totally different feels. It has more of a "house rules" feel to it than a rigid system.

Mech Warrior has a ton of rules that you need to learn before you can really get going.

Vampire is primarily centered around role-playing, D&D, Star Wars and GURPS have a nice mix of role-play and combat, and Mech Warrior is centered around combat with less real role-play to it (really, almost none). Shadow Run is slightly more combat than the big ones but less than Mech Warrior

good ideas so far, any other suggestions? and @tru, the way d&d uses miniatures was always a bit off-putting for me. is this really necessary?

"The fun-factor and ease of rules of the d20 system cannot be under-stated. "
"The benefit, though, is if you decide to go with a slightly older edition (like D&D 3.5") (snipped)

I totally second this. D&D 3.5 is one of the best and easiest systems, and has the benefit of being an extremely well documented setting. Pick up and play.

And no, miniatures are for people without imagination ;-)

Btw, if you're flexible on setting, I can also warmly recommend Vampire. The system is even more easy than D&D, but it's not classical fantasy.

A full field of miniatures can help with the tactical nature of combat, but then it can also overshadow the RP nature of the game. D&D 3.5 and Paizo's Pathfinder are pretty similar, though I think Pathfinder might be simpler, even if I don't like the setting as much. But that's their lore, and you can really do whatever you want with it almost as much as you could in 3.5.

Fate is a pretty versatile system too if you're looking for more freeform and RPG than dice-rolling.

For fantasy, I think D&D is probably the best. But you can find so many retroclones for free/cheap now, just decide which edition you like and find the corresponding retroclone.

Also, the BRP system is pretty simple and easy to learn...the one CoC is based off of, but used in it's raw form for fantasy, percentile based...

AVOID D&D 4th Ed. It's terrible. The change of measuring distances from feet to "squares" has reduced elements of it, especially combat, to a glorified boardgame.

The Dresden Files RPG is heavy on story, and light on dice, and could probably be adapted to any situation.

@jamiet: yeah, whenever i read something like "can attack characters than are one square away" i cry a little inside.

i decided to go with gurps for now, which will take longer to setup, but is easier to start with as a player, because of the cp system that helps the roleplaying factor.

For reference, the tabletop RPGs I have the most experience playing and/or running are:

- AD&D (2nd Ed.)
- D&D (3rd Ed.)
- Call of Cthulhu (mostly 3rd Ed.)
- Deadlands
- Warhammer Fantasy Role Play (1st and 2nd Eds.)
- Judge Dredd RPG (The original Games Workshop d6 based version, not the later d20 system one)

The games I play / run the most these days are:

- Judge Dredd RPG
- AD&D (2nd Ed.)
- WFRP (2nd Ed.)

Corporation has an easy-to-use 2 6 dice system (I think it's something like six pages that describes how to resolve all rolls) and is somewhat adaptable. It has Psionics instead of Magic and is heavy on tech.

How about FATE?