Don't worry about it. Filtered just means that you're firewall is blocking those ports. If you scan yourself locally, you're scanning through loopback and the firewall never plays a part. When you scan remotly is when you'll get the real results.
While we're on this are all those open ports necessary? Do you have to run your own DNS server and imap2 server? If not you should look into closing those off. Also, think about firewalling off mysql, it won't hurt the server if you're using localhost as the servername on whatever scripts are using it.
Just a few thoughts