Root noob questions

im running on giant punes kernal o. virgin.... and ive read so.e on over and under volting it i trigues me and as far as i can tell from a few apps and this forum gp's kernal doesnt support it. is there a second kernal that would allow me play around with this just as a lrlearning experiance? and would i be able to keep gps kernal on the internal sd and reflash if there was an issue?
as an additional thought what would i need in order to start atempting to build myself a personal rom from the hydra build? i am unfamiliar with the "kitchen" and other terms used and do intend to research more later
and as one final question, if my device becomes unstable am i to understand a nandroid recovery will alow me to go to last known good condition and try again so long as i backup before any change whatsoever?
i apreciate any awsers and apologize for im certian ive missed things in my searches im useing the phone app and still gettin used to its ins amd outs

 

okay thanks guys the rom thing i was thinking ahead on lol...il have to build a pc for it lol so ive got all the time on the world to read up on it more beforehand lol.....
od rather not chamge roms just yet id have to het a little more educated but the cm9 /miui does that allow more finite easier to brick controlls? uv/ov oc to 1.7(ive read the dangers) lol i want to do things because i can like any other noob-rooter im sure! lol