Hey bkribbs,
It looks like you should be able to transfer files in TightVNC - look in the drop-down list in the top left hand corner of the "window" border...
If not...
Are the computers connecting through the same router? If so, I would just setup a Windows home network and enable file sharing on the computers.
.
Here's a nifty little walkthrough from the good people at MS:
http://www.microsoft.com/windowsxp/using/networking/setup/homenet.mspx
Post back if you have any questions or problems.