Just unzip all the files into whichever folder you wish the game to be installed (i.e. C:\Program Files\WinPac 2, or something
If you don't unzip with a program that supports long filenames, you'll need to rename WinPac2.dat back to WinPac2.data. Programs that do handle long filenames (such as WinZip) should extract it properly.
If you want a shortcut to the game on your desktop or Start menu, you'll have to create one yourself. If you need help with this, please consult your Windows documentation or e-mail me at WinPac2@dauwalder.net.