Connecting Mac and PC to Airport Extreme

Trying to migrate some files from a PC to a Macbook and am having trouble. After many failed attempts, it seems to me the best way is to connect both the PC and the Mac directly to the Airport Extreme. I am asking if this is possible, will it work to move the files from the PC to the Mac and how to set it up correctly? Below are details on setup now, problems and various solutions, although just showing me how to attach both a PC and a Macbook to the Airport Extreme, is my primary need now.

NOW - The PC connects directly with Ethernet Cable to Airport Extreme. Airport Extreme connects directly to the ISP provided Cable Modem. The PC also connects directly to a Printer with a printer cable.

The Mac connects by Wireless to Airport Extreme (and Internet) and to to the Printer.

This arrangement is a result of the PC, more or less, falling apart. The PC wireless connection usually will not connect or fails, therefore I opted to use the Ethernet connection. By necessity, a D-Link is used in place of the two broken USB connections on the PC. Due to condition of PC, I prefer to leave everything as it is since it's working so far.

POSSIBLE OPTIONS - When I looked at various ways to move the files from PC to Mac, it seemed best to use an external hard drive, but I've not tried that yet since I am not sure how to change the drive's PC format to the Mac format without losing, in the process, all the files copied from the PC. I bought a new external drive that is supposed to work on a PC or a Mac, except that, with this PC,there is no assurance the drive will work. Two others I used as backup drives no longer can be found by the PC.

I tried to set up a network with the PC and Mac, but never succeeded.

Also, tried the file sharing instructions and never succeeded in that. In both cases the Mac just did not show up on the PC network places, nor does the PC show up on the Mac, despite my following instructions as well as I could.

That is why I would like to take what seems to use a more direct route to get the files I want from the PC to the Macbook.

Thanks in advance for any help you can provide.

Don