When I went to school, my current job (network admin) didn't even exist.
I went to school for computer repair. As in- find the bad component on this circuit board, unsolder it and install a new one. PC LANs wouldn't exist in any meaningful way for several more years.
I owe a lot to the sheer luck of timing. I had a good base of knowledge when PC LANs did roll around and I've just been adjusting to new technologies ever since.
My memory is shaky on this, but I believe quite a large number of machines with OEM Vista licenses shipped with XP installed, via downgrade rights. I know the organizations I was working with at the time bought quite a few HP machines configured this way. MS kept extending XP's availability in this way, somewhat masking the almost complete lack of interest in Vista for corporate clients.
What failed to happen was a mass migration to Vista by corporations. They mostly just waited for Win 7.
I believe the concept of "pre-existing condition" only comes into play when changing providers. Since her diagnosis occurred with our current provider, she's covered for that diagnosis (she still gets regular (and expensive) screenings) as well as future health issues.
Also, disability insurance should be considered in addition to health insurance. It isn't horribly expensive and the younger you start the policy, the less expensive it will be.
I got an individual plan from the same provider that my company had been with. It was really pretty simple. Not cheap, but simple.
I'm damned glad that I did, too. My wife was diagnosed with breast cancer a couple of years later (she's fine now). We would have been wiped out if not for insurance.