Sure,
1. Open the 3com Image editor and create a PXE menu. This file is the bootstrap that will load your Dos images.
2. Add your images that you created w/ the ghost boot wizard or converted from floppies (or whatever)
3. Make a wildcard entry composed of all ???????????? - this will provide the same menu to all clients. (feel free to change this later).
Leave the PXE & TFTP programs running as Apps so you can watch the file paths and make sure they are correct. You may or may not need to tweak your tftp's root folder and make sure it's consistant. You'll be able to see really quickly if there's a problem. After you get everything running then close them and setup up as services in Windows.
I strongly recommend ditching the 3com tftp server. I've had great success w/ tftpd32, and others on this forum really like the solar winds tftp.
Good luck. Cheers,