Well, the easiest thing for you to do it read the Howto at
http://www.linuxdoc.org , If your completely unfamilar with the kernel, best thing to do is get the instructions from teh how to source. Either that or by the latest version of Suse that comes with 2.4 kernel, but me personally, don't use Suse and would recommend just reading, then installing/compiling.
Good Luck.