what it is you are asking here. Are there two distinct questions, or one?
If what you want to do is physically connect two machines and transfer files etc. then you don't need Laplink (or any other third party software) because you can do the job within Windows.
If the connection is going to be a remote one, i.e. you are going to dial in to one machine from a remote location, then you do need a software solution. Fortunately, there's a solution available (Free) from Microsoft, in the shape of the client portion of the remote desktop facility that's included with WindowsXP Pro. You can install the client service on any machine running Windows 95/98/98SE/ME/NT 4.0/2000 and thus be able to dial in and control your WindowsXP desktop remotely. What you can't do is use the XP Pro machine to dial into the machine running Windows 2000.
If this interests you
click here where you'll be able to download the software. There's also a helpful walk-through of the setup routine.
As far as the transfer of the MP3 tracks is concerned - you can simply drag them from one machine to the other, once they're connected. If the connection is a remote one you'll wait all day while two CDs full of tracks transfer, but that's another problem.