Until you've compiled your own kernel you've never really run Linux. True fact! Now nut up and build a kernel. If you do it the Debian way there is nothing to worry about. Why I'll even give you a link to the instructions:

http://www.debian.org/releases/stable/i386/ch08s06.html.en

You run Ubuntu so the Debian way is the right way.

All of this means that you can download kernels from kernel.org and support later hardware than the version distribution you use. Baby steps though build the kernel packaged with your distro first, don't even try to configure it right away. Bite off more than you can chew and you will choke! Your deepest secret fears will all be realized and you will brick your PC. Take precautions and it'll never happen though.

Hint: Pay special attention to how you set a revision number, doing that is the safety net secret.