My recommendation:
Use D&D 3.5 (I prefer it to 3.0 now that I've given it a chance) and find conversions for your old D&D material online if you need it. Otherwise, the web and, curiously enough, D&D minis can greatly simplify the need for statblocks which is probably the primary hurdle in using materials from older D&D editions. There are tons of statblocks already out there on the web (for instance, the d20 100 NPCs thread in the rogue's gallery
http://www.enworld.org/showthread.php?t=99643&page=1&pp=40
or blackdirge's souped up, buffed up monster thread). And, if you have D&D minis, each one comes with a card that has RPG stats for the mini. Thumbing through a few of my cards, I came up with stats for a Ftr 1/Mnk 6, Clr 3 (of St. Cuthbert), Clr 1 (of Dol Arrah), human War 3, and a half-elf hexblade 7.
These can be exploited a bit more fully once you know the system. For instance, a statblock for an orc warrior could easily be used for a human warrior--just reduce his strength a little bit, assume he's a bit dumber and ruder than most, and then give him another skill at max ranks and a skill focus feat in it. So, the human to orc conversion works out to: Skill points: add either jump, climb or ride at character level +6 +dex, and reduce strength by 2 (atk -1, damage -1 with a one-handed weapon). Result: a dumb and unusually rude human of the same character class. It's easy enough to even do on the fly. Premade half-elf NPCs are ideal for this: they can be converted into humans with only the addition of a skill and feat (which probably won't come up) or into elves by changing constitution and dexterity (AC, fort, reflex, init, hit points).
That leaves you with all of the advantages of 3.5 in balance and customization of characters and minimizes the disadvantages.
As for the rules arguments, etc advantages, I don't think you'll actually find that to be too different in systems with fewer rules. I remember I had far more rules arguments in 2e than I did in 3.x. Part of the reason is undoubtedly because I'm no longer in junior high/high school. But part of the reason is also because the rules cover more situations. "Can I jump on the table and hit the orc from above?" Sure. DC 10 jump check to hop up onto the table and +1 to hit for higher ground. Under 2e, it would depend on whether or not the DM had been turned down for a date that day (or whether the sky was blue, his bike had got a flat tire or someone else got the last pizza slice while he was still hungry) whether it was a strength check, a dex check, no roll needed, or straight up impossible if you're wearing armor. Everyone thinks they're reasonable and consistent but few people are as reasonable or consistent as they think.