Moved: This thread is more suitable in Linux-Newbie and has been moved accordingly to help your thread/question get the exposure it deserves.
I understand you want to make a number of changes, but use the same kernel you have now, the one that came with your distribution, right? If so, install kernel package from your installation cd. The package name is probably something-kernel (my quick search doesn't show me the name, but it should be quite easy for you to find it on your instalaltion cd).
When it is installed (to install use 'rpm -i package.rpm' command) you have the sources probably in /usr/src/linux. Now you need to make decision which tool you will use to reconfigure your kernel (they give you the same options, but look differently). You can have a graphical config (will work only if you have GUI installed and running on that machine), text mode with menus or plain text mode. Before you start, check if you have compiler (gcc package). If not, install it, it will be needed. Now whcih configuration method do you prefer?