Here are the various options for module groups and their individual modules. To see these options applied, check out Options Demonstrated.
Gutter Width: This is an option that is set as a global value in the skin constants and cannot be adjusted on module instances individually. It provides how many pixels of gutter should be between columns or modules.

Distribution: This is how the modules are porportioned ("Half Half," "Quarter Quarter Half", etc.)
Space Before and Space After: DEPRECATED: These two settings will be eliminated in the next version of the QuickSIte. They were basically unneeded as space before and after can be set in the same way as with all other TYPO3 content elements.

Show Title: A value is set globally to show or not show module titles by default. The default can be overridden by the user on a per page basis.
Bleed: Causes the content to bleed. Adds a class to the module body for bleed and changes the max image width. See also module feature image.
Unframed: When checked the module will look like a column. Allows you visually to have columns next to and between modules.
Gutter Width: This is an option that is only set as a global value and cannot be adjust on module instances individually. It gives how many pixel of gutter should be between columns or modules.