49ers biggest rival - Now, Seahawks. All Time, Cowboys and maybe Giants
NFL's most hated team - Right now, Seahawks.
NFL's biggest chokers - Hard to say really. I'll go with those McNabb Eagles teams tho.
NFL's most competitive team - Probably the 49ers.
NFL's best QB - Montana/Marino and honorable mention for Elway (dude was clutch and always had s**tty teams playing well)