Try PC Security to lock your folders, PC Security can do more than that.

Download : http://www.downseek.com/download/5740.asp

And for the Floppy Compression without any Compression Software installed, I dunno if this will work, but Windows comes with a "Backup" utility, try to backup the files you want to compress. If its not too big, it might fit into the floppy disk.

Accessories->System toolls->Backup

CB-Byte