You could install it when you're connected to the network, and then move the OOTP folder to your local drive as described here:
http://www.ootpdevelopments.com/boar...d.php?t=142326
http://www.ootpdevelopments.com/boar...d.php?t=143247
Or install OOTP on another computer, copy the My Documents/SI.../OOTP... folder to for example c:\ootp2007 on the laptop, and change the OOTP user path on the laptop as described above.
Good luck!