think of a zip file as a suitcase.. it's one package that you can put a lot of things in and carry as one.. otherwise, you'll have to download/transport all of your socks/shirts/etc separately..
here are the direct links to the zips you need (2 separate zips) --
LibFredo 3.4b.zip:
http://forums.sketchucation.com/download/file.php?id=34712
FredoScale 2.0g.zip:
http://forums.sketchucation.com/download/file.php?id=27660
you can unzip on your desktop and move the files into your plugin folder (and i actually suggest doing this just so you can understand what's happening)
when you unzip LibFredo3.4b, you will have two items:
a folder named LIBFREDO6_Dir_34
a file named LibFredo6.rb
when you unzip FredoScale 2.0g, you will have two items:
a folder named FREDOSCALE_Dir_20
a file named ZLoader__FredoScale.rb
take the 4 items that i've highlighted in red and move them to your sketchup plugins folder --C:\Program Files\Google\Google SketchUp 7\Plugins\ -- relaunch sketchup and the plugin will be installed.