[X-Newbies] Spotlight settings

[J]

I have put my whole HD into the Privacy pane on Spotlight and no  
longer have problems with mail messages not showing up in the preview  
pane! This was done as a troubleshooting method but now I like it  
that way and will keep it except for one folder.

How do I just add the Documents folder for example, for it to index?  
I do not want it doing a two hour indexing of the whole drive.

I suppose I will have to drag individual stuff to the Privacy and  
then leave out the Docs folder but this seems backward to me.

The checkboxes are just what will be displayed and not indexed? Or yes?