I think they should really allow users to take advantage of the "modular" nature of Windows' core by letting users control the kind of setup they want/need.
Instead of shoving/forcing us their idea of what we want/need (read: Home, Business, Ultimate, etc), they should tweak Windows' core to allow a more barebone setup to function. By doing so, they can accommodate alot more users, from the uber/cash-strapped to the budget-concious users, in terms of the kind of hardware the users have/can afford.
Let's take a look at Vista's services. Let's face it, alot of these services just don't provide enough, tangible benefit to the common users, more so when one considers the cost in terms of performance drain. These services should be easily customized before installation. But how do you control the experience of the user w/o forcing them these services? Simple, you already have two ways of doing so: 1) Default Settings: if you truly understand your typical user, you'd know that they would hardly tweak things, leaving things as it is; 2) Simple warning messages/pop-up message boxes: these should give them some idea as to what is being traded-off.
Again, give the users control of what they want to install. DRM-infected components? I'm happy w/ DVD. Indexing? I don't need it so why force it to me in the first place.
Sorry for the long message.