1.Go to control panel and Automatic updates and put it on automatic.
Type gpedit.msc and OK.
Go to Computer config. Right-click Administrative Templates, and click Add/Remove Templates.
Click Add click Wuau.adm from the list you see, and then click Open.
Close window. Now you have Windows Update in Administrative Templates>Windows Components. Check it out.
3. Hard way (well, not THAT hard but anyways...)
Regedit. By regedit you can change the values to enable\disable the service.
...last resort, but only if you know what you are doing...
If you choose this, I'll give further instructions.