Well, I'm not sure that I believe that you actually use OpenOffice to edit code, but here's my standard example of something I can do much faster in vim than people can in other editors:
Imagine you have the following line of code:
$welcome_message = "Welcome to my site!"; // message displayed at the top of the main page
How would you go about changing the welcome message?
Most people I know would use a combination of Home, End, Backspace, Shift, and the arrow keys to select or delete the string, and then type in a new welcome message. Some would reach over to grab the mouse and select the string, then type over it. In vim, I just need to get my cursor between the quote marks (and there are many ways to do this, personally I'd probably use a quick find and then a couple pushes of w or e). Once anywhere inside the quotes, I just type ci" (a 3-part command, change inside ") and it erases everything inside the quotes and puts me into insert mode. I can easily do this faster than your hand can even get to your mouse.
Yes, vim is hard to learn, and it's frustrating for quite a while. But once you start actually understanding the "language" of its commands and how they fit together, you'll wonder how you ever used anything else.