Hi,

the exact styling of modules depends on 3 things:
1 - the exact html used as the modules are output
2 - the class names of the different html elements involved
3 - the CSS applied to those HTML elements, usually from a CSS file imported into the page.

The various options in MetaMod simply affect [1] and perhaps [2]. Your template can make further changes to [1] and [2], and is completely responsible for [3].

The 4 options for "Style for included modules" change the way that the HTML is generated which surrounds the modules that MetaMod includes.

I think the best way to make the modules appear horizontally is to inspect the HTML generated when the MetaMod includes 2 modules, and to inpect the page using Firefox's FireBug extension. Then you can dynamically alter some of the CSS parameters affecting the modules to see what will make them line up side by side instead of vertically. Once you know what parameters to alter then you can add these to your CSS file.

Don't forget the use of the CSS Class Suffix in the included modules. Try adding a suffix to the 2 included modules (i,e. edit those modules, don't change it in the MetaMod module), then inspect the page with FireBug. This will probably help to isolate the modules in question, so that the CSS changes apply only to them.

MetaMod is not really a layout tool, it's more about the selection of exactly which modules are going to get included on the page. The hints above are just general Joomla advice.

Best regards,
Stephen