How can I display the members of a group?
There's more than one way to view the contacts added to a group, here are a few, all of them will list the contacts belonging to the searched group.

Option 1) Navigate to Search -> Find Contacts, select your group filling the field in any group, leave the rest of the fields blank and hit search.

Option 2) Navigate to Search -> Advanced Search, select your group from the Groups field and hit search.

Option 3) Navigate to Contacts -> Manage Groups, here you can search/create/delete groups, on the right hand side of the screen there's a Contacts button for each created group, click it.