I've no idea why I didn't do it before, because it's very convinient. It's missing a couple of features, like as the key settings, but it's extensible, so I'll add that later.
The reason why I've implemented it right now is because there is no menu yet in the game, but I want you to be able to fine-tune the settings for your preferences. Oh and I've also added a temporary option to try out cooperative gameplay. It's just a temporary solution because there will be a nice menu later on, of course.
Here, have a look at the config.ini, I think it's easily understandable:
# Pacaman configuration file
# Resolution width, height and bits per pixel
resolution 800 600 32
# Fullscreen 0 to set it false, or 1 to set it true
# Vertical sync 0 to set it false, or 1 to set it true
# Tilesize 32 or 40 or 48
# Music volume in percent from 0 to 100
# Sound volume in percent from 0 to 100
# Cooperative mode 0 to set it false, or 1 to set it true
# Show frames per second 0 to set it false, or 1 to set it true