I know you asked for a windows GUI client, but in case you don't know about it, phpMyAdmin is really the way to go for pretty much anything you want to do. It is a web application that runs on php, is totally free, and works flawlessly. It has to run on a web server, but it doesn't have to be on the machine where the database is, it could even be installed on a machine in your house (preferably a nix/apache setup).
GUI clients that I've seen all have quirky little bugs and occasional slowdowns or lockups, and all but a very few are commercial apps (not free). Try the QueryBrowser from
