Try something like this:
select top 5
topic_id,
t_subject,
m_name,
t_replies
from FORUM_topics ft
inner join FORUM_members fm
on fm.member_id = ft.t_author
where t_date like '200308%'
order by ft.t_replies desc
Probably need to use ASP to build the date string first, format - yyyymm.
Works OK for SQL DB, might need advice on adapting for Access or MySQL though.