You are to the point where you can finish between sips of coffee.
Stock distro kernels are generic monsters built to suit almost every machine configuration on the market. Build your own, you can do it before the coffee brews in the morning.
I can't help you w/Grub, though the syntax looks straight forward. It probably is not a good idea to replace the current kernel, just add in the new one and have a new boot choice. Sometimes it is nice to try something out first. And hey, everyone needs a few kernels around. An easy way to make a boot floppy is the following:
First put a floppy in the appropriate floppy drive then issue:
dd bs=8192 if=bzimage of=/dev/fd0
(Note that this is the same as running "make bzdisk" as described in /usr/src/linux/README.)
Then, potentially, your computer should boot from the new kernel. Good way to test a new kernel.