There are several ways to deactivate CapsLock or give it a new function. I used a AutoHotkey-script for a long time but utilizing the Windows-registry is the cleanest albeit not easiest way to do so.
This is were SharpKeys comes into the picture. It's a small program which lets you change the function of any on the keyboard and makes the necessary changes in the registry. You don't even have to install it, it works out of the box.
|CapsLock is useless and my LAlt is broken.|
Just select the key which function you want to change and then select the new function. That's it. Reboot and you're done.