11 Dec. 2013
The answer will vary depending upon what you want to back up.
I don't have any pictures or other documents attached to my PAF data, so the zip file that PAF creates when using the PAF backup feature contains only a compressed copy of the .paf data file. I don't know what it would contain if you have pictures, etc. attached.
So another way of backing up your data is to just copy the .paf file to a flash drive. And as long as you're at it, export your data to a gedcom and copy that to the flash drive also.
If PAF also gathers up any pictures and documents attached to your data and includes those in its back up zip file, then you'd need to add those to the flash drive.
A two step process would be to use PAF's back up to gather everything into a zip file, if that's the way it works with pictures, etc., then decompress that onto your flash drive. Most of the newer versions of Windows (XP on up) will let you drag and drop out of zip file and on to a flash drive.
Dave