Hi,
I use VNC (Virtual Network Computer)
http://www.os2site.com/sw/internet/remote/ on the server I have here downstairs as well as some Win boxes at a clients, and PM-VNC pmvnc104_ow.zip on my main PC here. Also allows me to sort out stuff on my wifes Mac elsewere in the house which comes with VNC as part of the latest Mac OSX versions.
For file transfers, I um, have a local network for that :-)
For one remote client I simply use FTP, plenty of FTP servers around and its easy enough to start from the server via VNC.
I use Peter Moylans FTP Server, available from Peters website at
http://www.pmoylan.org or various other places including
http://www.os2site.com/sw/internet/ftp/Cheers
IBM