The DiskUtility options are not enough to keep your system in good shape.
You need DiskWarrior or TechTools.
Those applications runs some deeper maintenance routines like rebuilding Directories or fixing the files "Finder Info".
I bought DiskWarrior back in 2005, when my brand new G5 was getting a Kernel Panic every 10 minutes.
Now I get one a year and my HDs runs as horses.
The best investment in software I've ever done: some 80 bucks paid 6 years ago and they keep it updated.