Did you not get any messages or warnings or any kind during this process? I might help if we knew which direction to look into.
As far as the Recovery CD, I do not use Homegroups so you might be right about it asking for a password, but all I have ever seen is the Admin Password for the Admin user, i.e. normally you. So now I suppose I need to check how something else works.
If you have the Install DVD, it does not ask for a password.
The Startup Repair, seen in the attachment, is what is normally used to fix the startup problems. It runs many of the required utilities to fix boot problems. If that is what is running, and it doesn't sound like it, it will normally take care of the problems.
But you need to be able to get into a command prompt using the Windows Recovery environment. If the F8 key or the Repair CD do not work, then you will need an install DVD.
Your system may have other options, I do not know.
Edit: You did not mention if you had any virtual drives, but if you do or you have more than 1 hard drive, you might want to check the bios to make sure your hard drive is listed as first in the hard drive boot priority.
Also, have you looked into using a bootable anit-virus? I am downloading one from
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