In YAST (Suse's system configuration program), there is a tool called the "Runlevel Editor". (if you upgrade to Suse 10, it has a different name in the Yast menu, but it's the same program)
Open this program, and you'll see a list of programs which can be set to start when the computer boots. They're in alphabetical order, so scroll down a bit, and you'll see an entry for mysql. Select this line in the list, and click the "Enable" button at the bottom of the form. This will start up your MySQL server immediately. Then click the "Finish" button, and the settings will be updated so it is started every time when you boot.
Hope that helps