How to use other voip sip softphones than skype in linux

[user1]

I am skyping with a friend who has windows xp and I am using lucid.

The video and sound is often broken so the conversation is often 
difficult to follow.

Then I tried aMSN and it tells that it will not do video.

Then I tried linphone and the sound did not work.

Then I tried Ekiga and could not make it work.

Then I tried Kphone and that I could not make to work.

So now I am back to skype.

Any good experience of using another softphone which is as easy to setup 
as skype and which works well?

It has to be easy to setup so even newbies can use it :-)