You don’t need to install an FTP client like gFTP or Filezilla just for some simple file transfers in Ubuntu. Nautilus has a built-in FTP client. Click Places>Connect to Server and fill in the connection information. The server will then appear in the Places sidebar in Nautilus. Alternatively, you can type a FTP location into the address bar like this:
If you need a more powerful FTP client, I would recommend gFTP (sudo apt-get install gftp).