What I do see that is suspicious is that the Fast PC first looks at a Norton key on step 2311. The slow PC hits it at 171. I think it would be worthwhile uninstalling Norton:
Download a new install of Norton.
Download and save the norton removal tool
Uninstall Symantec (save the product license key since you want to reinstall it:http://us.norton.com/support/kb/web_view.jsp?wv_type=public_web&docurl=20080710133834EN&ln=en_US)
Run the Norton Removal tool.
Install Norton, put in your license.
It's possible that it's just a config setting in Norton - I refuse to use Norton so can't help you with configuration. It's also possible that Norton is not running correctly on the fast PC and that is why it is so fast. Norton is known to slow down boots.