You can customize your GTalk to function the way you want it to. By default, you should see all your friends photos next to their screen names, when you login to GTalk. However, there are possibilities that you will not see their photos next to their names.
1> To enable this feature, sign in to your Googlt Talk (GTalk),
2> You’ll notice small View Button at the bottom of your friends list.
3> Click this button and Check the option Show Pictures. Checking the option will ensure that you will be able to see the photos of all your friends next to their display names. If you Uncheck the option, then you will not see their photos.
To see the list of only online friends, follow this:
Now if you want to see the list of only online friends, then uncheck Show Offline Friends option and the list in your GTalk will have only online friends.