I suspect this is me that Peter is talking about, but I fear he misunderstood what I was trying to say, to begin with the advice above is without question the wisest way to cover yourself, and it is something I have yet to achieve, the last time I tried (several years back now), and was far more complex than now (from what I saw), this is pre 1TB drives, and external USB ones, even if it was just cost making them out of most people's reach.
How this started was because I warned him of the big Nvidia issue affecting many people of late (me included), as he had mentioned about updating this driver, I had suggested NOT to update, more so if he was stable, due to the masses of people affected by this, but he had done it before he saw my warning I think, and all I had said was that IF there was a problem after doing that, he should try and use the Roll Back Driver option in the device manager before he started recovering the entire system via his backup's.
My logic behind this is simply why make something harder than what it could be, I also included a comment about read\write and drive life being shortened each time this was done (I was mainly thinking of SSD's here, but is true of any disk), although I also conceded that most would never be aware of just how much this would affect them, because a drive can up and die at any time, the lifespan quoted by makers is purely based on an average, no one can say just when it will give up the ghost, it's luck of the draw if you get a good one or a bad one.
But the long and short of what I was trying to point out, was quite simply sometimes a simple fix is just that, simple, with the image back up you have little need to worry, if the simple fix does not help out, you still have that as an option, so there is nothing to lose just trying the simple options before re-imaging the entire system, so roll back for drivers, or system restore if needed, with an image in reserve there is nothing to lose. 
