If you don't mind paying for it, Dark Basic is a wonderful piece of software for game creation, practically limitless in terms of creativity. The up side is that it's centered around game creation, meaning it's easy to make simple stuff (read: easier than learning the basics of C++ and slowly crawling your way up the ladder towards making full fledged games).

The down side is that, since you get a packaged engine, there isn't much upgradability...but everything I've seen done has been quite impressive for a package I payed $30 for. Now I just have to get that whole...y'know, 3D modelling thing down -_-