Right. Microsoft has to include drivers for every single configuration out there, because the whole 'point' of Windows is to be ubiquitous, which Microsoft has been pretty successful at.
Yeah. I had a Windows 7 PC for about a month earlier this year, and I have to say that for Windows, Win7 wasn't that bad. It was still Windows, and I still found it annoying, but it is an improvement over previous versions of Windows. XP is still more stable, in my opinion, but once Win7 becomes more mature, it might be better in that regard.
And yes, the OEMs do love stuffing a bunch of crap on to their PCs. My Acer came with a load of useless software installed, and I ended up having to delete all of it. Ad-supported MS Works? MS Office trial? Dozens of other applications that I would never use? The same applies to the Compaq I had several years back. Apparently PC OEMs haven't learned a thing. As compared to my MacBook Pro, which didn't come with any ad-supported, bloated software, just the OS X default apps and iLife.