Check out pureftpd at www.pureftpd.org.
I think you can download GUI frontend for the server. I don't use any GUI on my Slackware setup, but I'm quite sure it has a front end. I setup PureFTPd within ten minutes after going through hell authenticating users using ProFTPd. Mind you, I have around 26 total hours of Linux experience, so if it was that difficult, I would not have been able to install it and have it up and running.