Transferring files from PC to Mac using external hard drive

I backed up my old PC using an external hard drive.  I now need to transfer some of those files over to my MacBook Pro.  When I plug in the hd it is recognized, however I cannot get the files to be recognized.  They are all zip files.  Please help.

If the drive was formatted for Windows it will be read only on the Mac. Download NTFS-3G on the Mac and that shoulld help. It may also have something to do with what you used to make the zip files. I don’t know much about Macs.