I have replaced Vista Ultimate with Win7 (64bit) since the day it was made available on TechNet on my Dell m1330 notebook. At first it was great and it really is just Vista but fixed (for the most part). I have had some BSOD originating from the network, but they only seem to come about if I am running Virtual Server 2007 (64bit) and power up another system on the same network. I also have issues with the nVidia desktop backgrounds becoming corrupted and forcing the video card to restart after a while, but disabling the background slideshow (which is a nice feature) seems to solve that one. I would say, as Betas go, this one is very good, so much so, that even with the issues above, I still prefer to use Win7 (and this is a Dev box, so it's thrashed very hard). I really dislike Vista (32 and 64bit) as it is a sluggard and, well enough said, you all know it by now...

Will Windows Steady State meet your requirements? http://www.microsoft.com/windows/products/winfamily/sharedaccess/default.mspx You set up your PC, configure Steady State, and then it protects the OS from getting written to. Then on a system restart, all the OS files are back to how they were initially setup. You just need to configure Steady State on the OS partition, and then have the users data on another partition that is not protected. Hope this helps! :)