Apple ID

I bought my wife our new iMac through the Apple OnLine Store. Because I made the purchase, they assigned me an AppleID and I assume logged the purchase against it. My wife has her own ID at the ITunes store and has her iTunes Library on a Windows PC. Will she be able to use her old iTunes Library on this computer (I know how to move it over)? If in the future we sign up for The iTunes Cloud service, will it update music on this computer?

Hope this isn't too confusing a question as I know what I mean but am not sure I expressed it correctly.

I can't answer your question regarding the upcoming iTunes Cloud Service as there still is much unknown about how it will work. However, I would "guess" that it will be cross platform and be able to update.

As far as your wife's iTunes library is concerned, the answer to that is yes. You might want to create a separate account for yourself on her new iMac unless she's going to be the sole user.

Thanks