www.gamedev.net is a place to go.
gamemaker (
http://www.yoyogames.com/make) might be of some interest to you.
1. Games are programs. Programing is making programs.
2. Blender is good. But 3d games might be out of your reach for now. Learn Blender, but start with something simpler (2d) as your first game.
3. There are a lot of them (just follow the links up there), but i have no idea if they are any good. I would second the idea to start with level editors. RTS games have some very good editors. Doom (or it's clones like hexen) is not a bad idea as it's simple 2.5D and has some scripting features.
4. no idea.
5. They're fun to play?