In theory you should be able to use samba. In pratice I've seen it sometimes work well and sometimes not. Let me offer another suggestion that may be a lot simpler than resolving the samba issue. Use FTP. Your roommate's system may already have a FTP server installed, if not you should be able to install and configure one easily. Once you have a FTP server up and running you can easily transfer the files that you want to save with Konquror as the FTP client in Knoppix. I'm not going to try to talk you through the exact steps for an FTP install and starting the srever, there should be plenty of other detailed info on the web.