I have two suggestions, both of which have quickstart rules you can look at to sample the game:
Riddle of Steel
http://www.theriddleofsteel.net/support/TROSQS.zip
This game has a brilliant mechanic called "spiritual attributes" that really help encourage roleplay. They are basically character motivations like conscience, drive (avenge the death of my father), or faith (Osiris). Characters are heavily rewarded for acting according to these attributes -- in a sense they serve both as action dice and experience points. It's really clever but hard for me to describe. The other thing is that combat can be very deadly. This encourages people to choose their battles wisely. In combination with spiritual attributes, which can grant extra power in combat, it encourages people to only take up the fight only when something really matters to them. It's great! I'd also refute that it's combat-heavy. If anything, I think it discourages too much combat. If you run the game with tons of combat, you will have to throw weak opponents at the characters or they will end up dead - however, when characters are thrown in the crucible, and things become critical, their spiritual attributes start firing they realize what is worth fighting for, and are given the power to carry it out. Think Inigo Montoya in the Princess Bride.
Lejendary Adventures
http://www.lejendary.com/la/downloads/LAqsRulesv106.pdf
Definitely old skool. Written by Gary Gygax. It's rules-light and allows a more free-wheeling, open-ended, approach to the game with characters described in broad strokes and lots of freedom for creative interpretation and improvisation. In some ways it recaptures the simplicity and fun of OD&D but is more elegant and flexible.
You might also check out reviews on rpgnet of these games. Furthermore, you might get better feedback regarding non-d20 games there too.
For what it's worth, I'll also back up Shadowlord and say that I do think that the system matters. It's not the only thing that matters, but you also can't just write it off entirely. Sure, a GM can run any type of game in any type of system, but some systems will make the job easier than others, depending on what you are trying to accomplish. At some level, there is a Pavlovian factor at work. What behavior are people being rewarded for? How does the game help you, as DM, reward the types of behavior that you prefer to see when playing? That's what a game system is for, right? To help the DM run the game?