I don't have a Windows 2000 computer, but allow me to explain why I would want information on upgrading one.

Vista has been the source of a great deal of worry for me over the past few months. I have a laptop that currently has Windows XP Home Edition. It's extremely important that I get Windows Vista on this laptop as soon as it comes out, strangely enough, for personal reasons. I don't know if the laptop's systems specs are enough to handle Vista (only a gig memory and 128mb video ram), but I'm sure it's far too early to know that for sure.

Because of the software pre-installed on the machine, a clean install won't work. The reason why I am asking about upgrading from Windows 2000 is that I have never tried to run an upgrade before, and I'm thinking my mind might be able to rest easier if I learn a bit more about how the upgrade process works. I searched online, but the only info I was able to find was upgrading from 98 to XP. Windows 98 is a whole different type of operating system, so it's no wonder that the upgrade process is a real headache. I know that Windows 2000 is really NT 5.0, Windows XP is really NT 5.1, and Windows Vista is really NT 6.0, so I figured that the experience of upgrading from 2000 would be more similar to what my experience may be like in upgrading to Vista.

So, assuming I have a Windows 2000 computer:

1. Can I expect some programs that would otherwise be fully compatible with the new OS to not function correctly afterwards without reinstallation?
2. Does the upgrade process erase the existing drivers? If so, is it still possible to re-install the drivers meant for 2000 to get the hardware working, or would I need XP-specific drivers?
3. Will the upgraded OS be as stable as a fresh install?
4. Does upgrading fail to add specific features?

Note that this laptop is used for web development, and will be used for college when I go in January. I play a few low-system requirement games on it.

I've used Vista Beta on a system with 1 gig and 128 meg V-RAM. Seems fine.
Regarding your questions:
>>1. Can I expect some programs that would otherwise be fully compatible with the new OS to not function correctly afterwards without reinstallation?

If you upgrade your OS (From 2000 to XP or XP to Vista) there's no reason why the programs shouldn't work, provided they're compatible with the new OS. For example, Norton AntiVirus 2001 works perfectly on Windows 2000, but after upgrading the system to XP, it stops working simply because it isn't compatible with XP. Norton AV 2003, on the other hand will work after upgrading from Win 2K to Win XP.

>>2. Does the upgrade process erase the existing drivers? If so, is it still possible to re-install the drivers meant for 2000 to get the hardware working, or would I need XP-specific drivers?

Yes and No. Yes, if the OS you're upgrading to has better drivers, no if it doesn't have the drivers. If the old drivers aren't compatible with the new OS, and the new OS doesn't have better drivers, the OS may just disable that device. Getting drivers specific to that OS will solve your problem

>>3. Will the upgraded OS be as stable as a fresh install?

If by stable you mean response times and general feel of the OS, then the answer is no. For a slick, fast OS, I'd recommend a clean install. Personally, I never upgrade. It's simply much easier to format and reinstall the new OS.

>>4. Does upgrading fail to add specific features?

No. An upgrade will install all the features of the new OS.

Thank you so much! I feel much better now. I know it's over a year away, but I tend to worry about things well in advance.

The reason why I preferred an upgrade was because I thought it might be a bit of a fight getting my laptop's applications restored, but I'm looking at my laptop manufacturer's website, and it doesn't look too hard to do a clean XP install, so I would imagine a clean Vista one wouldn't be much of a problem.

The reason why I'm worried about my video card is I have a 1920 x 1200 screen, and I figured that my video card couldn't run Aero glass without lowering my resolution. The LCD monitor looks really poor at other resolutions, so this would mean I would have to run regular Aero, which I've been told looks very ugly, and I have been unable to locate screenshots for it to see it for myself. I heard that the minimum requirement for Glass at 1600 x 1200 was 256mb, but maybe that's changed in Beta 1?

I really don't have much info about Vista, but I am intrigued about why you want to run it so much. Are there any major features that you want from it?