About how long does the whole process actually take? I'd say that W2k takes on average about 45 seconds to one minute to boot on adequate systems. Maybe I should time it just to be certain.
The bootup procedure usually goes smoothly to about 50-75% and then starts to initialize devices that can take a while. USB devices I've found will slow bootup a bit. Some cheap CDROM drives will drastically slow the boot process, especially if you leave a CD in the drive. If you leave a scratched up CD in the drive it'll take a long time to initialize it.
I've never heard my hard drives powering down during the boot sequence though. Are you certain that's what's going on? You know, I seem to have a very faint memory of somebody having a problem with hard drives powering down in Win2k......hmmm... can't quite remember.
I like to disable every damn power management option in the BIOS. It's not enough to simply set "power management" to "disable" either, sometimes you have to go through and disable all sorts of shit. This always seems to improve system reliability as long as you have Win2k running as a Standard PC and have APM off. You can also get rid of the "hold the power button in for 4 seconds" crap when you're not doing ACPI. It's best to run the system as a Standard PC to better manage your IRQ settings as well.
I will not suggest any other win2k "tweeks" because I have yet to find any that do anything useful. I don't even recommend the pagefile trick anymore. There are some settings that I like to make however, like disabling animated windows, but that's not much of a tweek

Oh, and I disable auto insert notification.
Win2k takes a while to boot compared to WinME and the like, but that's just the way of it. You should time it and let me know. It's sort of a small price to pay. Once nice thing is that you can leave your system running for extended periods of time without performance or reliability issues. Also, it isn't necessary to reboot as often...in fact rebooting because of a lockup is VERY rare (TIP: ocassionally a process will knock out the entire desktop. Ctrl+Alt+Del->Task Manager->Applications->New Task->Explorer.exe will get you running again) My favorite feature is being able to do *anything* to my network setup without having to restart the system.
Anyways, if your system truely is taking too long to boot, then the standard troubleshooting procedures apply. Just FYI, I've had to replace more CDROM drives in the last year or so than I've ever had to replace prior. In a couple instances the drive was making Win2k act funny, and in one case actually causing the boot sequence to freeze or appear locked for an irritating amount of time.
And for anyone reading, please be aware that the bootup and shutdown procedures of the operating system are absolutely critical. If you power the system down early during shutdown, or power the system down during bootup, you risk losing your operating system. I recently lost a Slakware Linux installation because I hit the restart button during bootup. I also lost a Win2k installation because a task had frozen and Windows was waiting for it to respond before shutting down. It is critical that you always let the system boot fully. It is just as critical that you not hit the power button if you shutdown the system and nothing *seems* to be happening. In this case, a process or two have either frozen, or are not in a place where they can be shutdown and windows is waiting on them. Be patient; sometimes waiting as long as 5 minutes. The system will eventually go down (assuming you're using a good OS; Win9x will often go to take a dump and never return). You know, this also applies when the system is just running...I've seen so many people inaccurately *THINKING* that their machines were locked up. Sometimes things go wrong, and sometimes it takes a long time to recover. Yesterday I had a goofy app start sucking memory and processor time to the point where the system was almost unusable...it took about 15 minutes for me to simply open up the task manager and kill the process...but I was able to do it. I'll shutup now.
Slackmaster 2000