Cool. I downloaded a couple. Some critiques.
For the Super Pacman, your mazes should have no dead ends. They should be open-ended. Although your version does make it harder since you can get stuck. Add some more sounds! Hee hee.
On 3D Zombie Rampage, its not clear what the object is. Kill everything in sight?

Kind of Doom-like, not bad! Needs to be controlled with the mouse.
I used to do this stuff a long time ago (in the stone-ages of microcomputers) in BASIC on the old Apple II, Vic20/Com64, etc. The last few years I picked up a few modern games books (Andre Lamothe, etc) and been trying to do this with Windows and C/C++. Quite a bit more complex.
Someday you’ll graduate to DirectX and OpenGL and get real confused like me!
I’ve done a breakout, asteroids, pacman, frogger (All GDI or DirectDraw games), and a primitive 3D Tank game with OpenGL. Most of this stuff you can learn from
www.GameDev.net or other places online, although with GameMaker a lot of the work appears to be done for you. It’s a start, but you’ll want to move up to C/C++ and then DirectX/OpenGL for the PC, or the C# language with the
Microsoft XNA Game Studio (FAQ page). Allows you to make your own games that will play on XBox. Though I haven’t tried this yet, sounds very interesting.
My games pages:
www.VazGames.com
www.VazEngine.com
Phil P