Sharepoint Import User & Profiles

Hi guys,

I would like to know if correctly. I'm trying to correct my connection with AD.  I already have the connection to AD but in the "User filter:" I would like to know if it's ok this query to exclude all disabled accounts and users start with "s-" because all users started with "s-" is a Service Accounts.

Exclude accounts that start with s-
(&(objectCategory=Person)(objectClass=User)(!(userAccountControl:1.2.840.113556.1.4.803:=2))(!(!givenName=s-*)))

Also I would like to know a best practice to syncronize the import schedule (Full & Incremental) for a Big Farm.

I supose this:
1- Full Every 1 Month
1- Incremental Every 1 Week.

It's OK?.

Is Sharepoint 2007.

Thanks in advance,