I'm pretty sure you're right by saying that it is creating the underlying connections to an unconnected network. this can create issues that are visible in verbose mode if there is no connection but it isn't something that should cause the boot-up of OS X to hang... it should just skip over it.

As for the helpful friend... ugh. sorry to hear. lets hope there isn't a next time.

Try to keep a backup of the kind of files I like to refer to as the "big-deal" files where later on, it would be a big deal not to have them. As for the DVDs going bad... I try to make two Install DVDs at a time and then only use one... that way I always have a backup (and I can make a copy of that one if one goes bad so I still have two).

Happy "acquiring"

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