RedHat 7.2, you're probably booting with grub. I use Lilo, but most of basics are the same. I'm a bit confused as to the question now, so here's what I do:
cd /usr/src/linux
(compile the kernel. To do this, read the README in the /usr/src/linux directory, or the HOW-TO over at linux docs)
cd /usr/src/linux/arch/i386/boot (where the compressed kernel Image is after you've compiled it.
cp bzImage /boot/ILikeCheese (Copies the image to the boot directory and re-names it)
Then edit your grub.conf file, which I think is in /boot, and add information for your new kernel. It will be the same info as whatever other entry is in there, just with a different name... oh, and you'll have to give it a different label.
Also, if you want to compile the kernel, grab a new one. I've got 7.2 running with 2.4.15,16,17,18 and 2.5.7,8 so its no big deal. The easiest way NOT to make a mess of your machine is to experiment entirely with a different kernel source than the one you have now, so you can always safely boot into your current kernel. Snag 2.4.18 from
www.kernel.org and have fun.
Cheers,
Finegan