I've seen this many times, but never gotten a solid resolution. A laptop takes a long time to process "preparing network connections" on bootup - before you even get to the login screen on XP. I troubleshot this today for a user who said it took 5 minutes to go through that when she was off-site. I timed it, and it was really only one minute and 47 seconds, but that's still an eternity.
Then I tested it when she was on-site. IT TOOK EVEN LONGER.
Then I went into Network Connections Advanced Settings (Network Connections -> Advanced -> Advanced Settings) and moved the IEEE 1394 connection below the LAN and WLAN connections. For some reason, it was at the top. Then on the next reboot, it was less than 20 seconds for preparing network connections.