Oil leak (maybe a cylinder head gasket?)

[allencr]

Leak? What leak?
It's a weep/seep, and unless it's a show car, I'd be crazy to do anything about it, it's completely normal.
Re-torque the head if you really feel like you've gotta do something. That's something IMO that should periodically be done on every aluminum head, but I'm only doing it for the headgasket's combustion seal, never for a slight smear of oil.
I think your chances of F'ing it up are real good compared to doing something actually useful.