Wireshark-users: Re: [Wireshark-users] Basic question about Wireshark
From: "news.gmane.com" <AndreasSander1@xxxxxxx>
Date: Tue, 26 Jul 2011 16:56:01 +0200
"Frank Walter" <francwalter@xxxxxxx> wrote in message 
news:00e201cc4b57$1f41b6a0$5dc523e0$@net...
> Hm. No, this didn't work.
> But when I set 'Capture Filter:' to "No Broadcast and no Multicast" in the
> "Wireshark: Capture Options" Dialog it works.
> No more broadcast packets are shown.

Are you talking about capture filter?
Unfortunately the capture filter syntax is different from display filter 
syntax.
The capture filter
  not ether dest ff:ff:ff:ff:ff:ff
should exclude broadcast packets.

> Now I discovered that I have all those packets from other wifi networks in
> my list.
> How can I filter them out?

If you talk about capture filter you can use
  ether host aa:bb:cc:dd:ee:ff
to get only packets from/to the specified host.