If you wanna have good quality and speed at the same time, I would suggest Gordian. You can download it from doom9.net.
I have been using it for like 5 months, excellent results, I must say.
It just takes some time to get used to.
At home, I have Athlon 1GHz @ 1.3GHz; 256MB 133MHz RAM; ATA 100 IBM HD and Star Wars Episode 1 encoded @21.5fps, Gladiator @ 22.8fps. Each film takes approx. 6 hours for 2-pass encoding.
Simply beatiful.