Install Navicat Lite from this site:
http://www.navicat.com/download.html
Make sure you download the one for Windows that is listed as Navicat for MySQL Lite. That is the free version. The other version is only for evaluation.
Setting up navicat is pretty straight-forward. And using it is just as easy. You can see all of your tables and open them and edit them all quickly and easily.
Then, just open your Accounts table and look for the status field for the account you want to make a GM, and then change that to 250.