Themes vs Custom Menus?

[MV10]

I finally got around to loading up and playing with the community installer. Pretty cool concept.

I'm sure this is a n00b question, but I had a look at the Wiki and didn't find a clear explanation of what the custom menus actually do. So that's my first question: do they add functionality, or replace it, and what do they do?

My second question is how they relate to the themes, if at all. I switched to the Carbon theme; would one of these custom menus pick that up, or are they a totally separate thing?

I didn't want to just wing it and install one, since (unlike themes) I didn't see an obvious way to return to the default in case I didn't like it or it screwed something up.

Thanks in advance.

[excal]

custom menus are different then themes. And are essentially user made menus. They're just a index.htm file that the pch will boot into inplace of the stock menu. They're very easy to remove if you don't like it.