Can Airport Extremes handle NTFS external drives?

OSX doesn't support NTFS Formatting -> NTFS is not supported by AE.

FAT32 or HFS+ only

Airport Extreme obscures the filesystem of the drive with the transfer protocols it uses. Your best bet is to format it with HFS+ (so you can have files larger than 4GB). It will then share the data with all the Windows machines using Samba. If you happen to get a Mac in the future it will connect using AFP (Apple Filing Protocol). You can have Macs connect using Samba too but AFP is a better choice. I have an Airport Extreme at my house and I have to say that I was very disappointed with the Samba implementation. I kept getting connection drops to the shares no matter what Windows PC I used. I ended up setting up an Ubuntu server on an old PC and connected drives both internally and through USB to it. It works perfectly now.

Since you have all Windows boxes you will need to use Linux to format the drive to HFS+. You can get the latest Ubuntu LiveCD and do it with GParted.