If more than one person wants to enter in a household and they have their own email accounts, can they enter a sweep like this? Will the administrators think it is one person because both entries came from the same computer?  I ask because my husband enters sometimes and I want to be sure he is not going to disqualify my entries.

Sometimes, if you're both entering from the same computer, you might just have to clear the cookies before the next one enters.  Some entry forms are touchy and won't let the form go through a second time from the same computer.