I was wondering if anyone knows what the best windows mobile optimizer or if there is way to do if for free.

Optimizer? You're going to be a bit more specific than that. Specifically, what are you trying to accomplish? You can alter the registry to change settings/behavior of the device to your liking. You can accomplish this manually with a registry editor but you need to know exactly what you're looking for or else you can screw up the device. There are other programs out there like Tweaks2k2 (google for the link) that have compiled a list of tweaks and will do the registry altering for you by simply checking a box but that program costs money.