How can i get the most power out of my MAC.

RAM allocation is dynamic and depending on what work you do, the effects will be
minor. Only working at large resolutions or doing long RAM previews will max out
RAM usage. However, I would dare a wager that the little RAM usage you see is
more to the fact that you have only 1GB. On such systems, the operating system
itself consumes most of the RAM and propagates memory requests by applications
to the disk swap file, only holding the bare minimum in RAM that is required to
run the application. It also depends on which auxiliary components need loading
(Quicktime, custom interfaces e.g. for Color Finesse etc.). This is further
disguised by the fact that whenever you change program focus, the inactive apps
are send to idle state, which consumes very few resources. Lastly, don't let
yourself be fooled by what you see in the system monitor. Various processes are
not listed at all in the default configuration and the probing cycle is set to 5
seconds, which in computer terms is eons. It's well within reason to assume that
one or the otehr peak is missing.