Hmm, it seems like you have payed no attention to TimOBriens post. What he explains is where the real problems come in. Doing a double partition on one drive can definately help the harddrive to run smoother while recording, but the heads still have to move for the windows programs. It is easier for the drive when it is double partitioned to keep the data organized, as in keeping all the windows data and the audio data in one group of clusters. However, you could easily experience dropouts running more than 12 tracks of 16/44.1 audio (maybe a little more tracks). Audio must be a continuelly stream for it to work properly. If there is a bunch of data streaming at once, then is all of a suddenly interrupted by a windows request, the stream will break, causing a drop out.
Of course you can get by with this, and so it is not required to have two drives. But this setup is highly recommended if you are doing it more seriously.
Yes mobility and safety is another reason for two drives, but usually not the most important reason.
As far as the Win98 vs. Win XP thing goin on here as well. It really mainly depends on your own hardware in your computer. The main factor between the two OS's is driver support. Yes, win2k and xp will run drivers more stabile then win98, but thats only if they are stabile drivers in the first place. If the company that makes your hardware makes good 98 drivers and sucky 2k drivers, then definately, 98 will be the more stabile OS. As far as blue screens and crashes, this is also another factor on your own personal hardware. Usually these blue screens and crashes come from incompatibility. Probably the biggest factor in incompatibility comes from the motherboard and or CPU.
So my opinion, is it is not far to call one OS more stabile than the other, win2k and xp most probably are the more stable and consistant OS's, but not for every system.
Darnold