The item table has the name.  I've posted some thoughts for a different user in this thread:

https://www-secure.symantec.com/connect/forums/i-need-create-two-more-colums-using-attached-sql-query-am-stuck

So if you have the GUID of the group, you join that to the Item table based on the SecurityGuid column:

JOIN Item ON ScopeMembership.ScopeCollectionGuid=Item.SecurityGuid

Select 'Item.Name' as the name of the group and 'Item.Description' as the description of the group.

Keep in mind that your query must have already narrowed it down to a single group.  A computer can exist in multiple views, with one group in each view.  Either that or be prepared for multiple groups.  The name of the group is just the last object.  So if your group names are not unique (e.g. Chicago\Workstations, Chicago\Servers, Boston\Workstations, Boston\Servers), you'll be confused since you only see the final level (e.g. a report would show Workstations or Servers, but not Chicago\Workstations or Boston\Servers, etc).