A little bit more info about what you are looking for would help.
But there are several ways to figure out what portnumbers are used on the network when you are using a Sniffer. Simpelest one is to look at the connection / session layer in the expert. Another possibility is to take a look at the decode tab were you can find the port numbers in the TCP (or UDP too) header of each frame. Also if these portnumbers represent well know applications, you can see in the matrix view wich application (this does not give you the portnumber, only the app. name)
Robert
Robert A.H. Wullems
Sniffer University Instructor
SCM / CNX / MCP
Citee Education
the Netherlands