It's one of those things that if you feel the need to ask, you don't need to do it. You'd know if you did. just keep up to date via yum. Distro vendors do a LOT of things to a default kernel to suit the system, so you'd realistically be taking a big step backwards if you stuck in your own vanilla kernel build without the myriad of patches Fedora guys apply.
As for bz2, do jxvf instead of zxvf.