select *
from foo
WHERE loc='002'
AND orig_date_time>TO_DATE('20060627235959', 'YYYYMMDDHH24MISS', 'NLS_CALENDAR=GREGORIAN') 
AND orig_date_time<=TO_DATE('20061127235959', 'YYYYMMDDHH24MISS', 'NLS_CALENDAR=GREGORIAN')
AND billed_year is null   
AND (foo_type ='Home' or foo_type='Inc');

index1 is on loc, orig_date_time, foo_type, billed_year
index2 is on loc, bar_from_blah, orig_date_time, billed_year