Hi toas,
I'm mildly chuckling (in a good way) at what you are letting yourself be dragged into as this thread progresses. You start off just wondering if installing Win7 SP1 is okay. Then you fire yourself into a process of trying different options to see if you can update the 'good' stuff and miss the bad stuff. Not the best way to go in my opinion. I have installed Win7 Pro. x64 SP1 on my computer and, after, now, several years of use, have never had a problem with it -- rock-solid stable. I have Win Updates blocked at a couple of points on the system, so this is never going to update, ever. Of course your system will be different from mine so that might not work for you. But if it was me I'd just try try the bare install of Win7 with SP1, see if it is okay, and don't tie myself in knots trying to work around a problem that doesn't exist for my machine.
Yup, this is what I avoid!
Yup, too! Don't dance with the Devil unless you are utterly, utterly pressed into it.
All the above said, having read this thread I do like the advice you are getting from others about how to update 'safely'. I've bookmarked this thread for my own use in case I ever need it in the future. But I'd never do it unless completely pressed to it.