Description of fields

Description of fields

Hello,

I'm looking for a description of fields available in Zoho and what their intended purpose are.  Obviously, most are self-explanatory but others are more ambiguous and I want to make sure we don't start out making simple errors which are never simple to fix. 

Case in point, I want to import 5 years worth of clients from our accounting software.  Some of these are old, one time deals so they don't really need to be clogging up the new system.  I would like to import the 1000+ accounts as in-active accounts and then convert them to active as we do further business with them.  The only existing field I see that might serve this purpose is called "Rating".  What is this Rating category intended for?  Is there a better solution for this?
 
Thanks