I won't get into this discussion of what's legal and what's not.
That's not my area of expertise, (I'm a technician, not a lawyer), but......
What I do want to suggest is that when you've resolved your "Legal" questions, make a full backup of your C: partition to either DVD's or to an external hard drive, to circumvent any problems you might have further down the road.
I mention this because you touched on the question of "what do I do if I have to reload my system"? (or something like that)
I always suggest that everyone, make a backup of their system, after the initial install and setup of their software, email, etc.
That will trump a factory re-install disk every time.
I'm constantly adding software and removing software from my own system, so I do a Ghost Backup Image file of my C: drive every week.
Good Luck,