If you are using vBulletin forum software, then create/add this to your robots.txt:
User-agent: *
Disallow: /forum/acp/
Disallow: /forum/announcement.php
Disallow: /forum/calendar.php
Disallow: /forum/cron.php
Disallow: /forum/editpost.php
Disallow: /forum/faq.php
Disallow: /forum/joinrequests.php
Disallow: /forum/login.php
Disallow: /forum/member.php
Disallow: /forum/misc.php
Disallow: /forum/mcp/
Disallow: /forum/moderator.php
Disallow: /forum/newreply.php
Disallow: /forum/newthread.php
Disallow: /forum/online.php
Disallow: /forum/printthread.php
Disallow: /forum/private.php
Disallow: /forum/profile.php
Disallow: /forum/register.php
Disallow: /forum/search.php
Disallow: /forum/sendmessage.php
Disallow: /forum/showgroups.php
Disallow: /forum/showpost.php
Disallow: /forum/subscription.php
Disallow: /forum/subscriptions.php
Disallow: /forum/threadrate.php
Disallow: /forum/usercp.php
Change /forum/ to your forums directory.
I won't go into big detail on why you need to add this, but if you look at the above, then you will see that most don't need crawling, such as sendmessage.php -- why let a bot crawl your contactus page, when it can be crawling your threads/posts.
Regards Jason
