I would like to transfer files between computers on my network

Unlike other users' questions, I would like to do something much simpler (I think). I have now installed Ubuntu 8.04 on all but one computer in my home network. Lets say Laptop 1 has user name lap1, Laptop 2 has user name lap2, Laptop 3 has user name Ubuntu (live CD), desktop 4 has user name desk4. All of them are running Ubuntu 8.04. If I am on lap1 and I want to see the contents on desk4. What do I do? I tried Applications -> Internet -> Remote Desktop Viewer but never get through. I tried gFTP, but never get through. I tried Places -> Network and see an icon of Windows Network. When I double click it, I get nothing. I would like to "synchronize" my computers or at least be able to transfer files from one computer to another. But I also don't want to have to specify each file in a terminal window that I want to transfer. Ideally, I would be able to click on places and see what is on each computer and then decide what I want to transfer. It might be something like mapping a network drive in Windows. In windows I use a program called pcAnywhere to do this and that program also gives me the ability to control the remote computer. This is ideal when helping my parents (> 80 years old) with computer problems. I am not so interested in transferring or communicating with Windows computers as my goal is to completely rid myself of Windows. Can anyone help?