One of my current projects involves reducing the number of old computers lying around. So far, the office systems have been downsized from 5 to 2. One system which had no data on it was dumped entirely, while three other identical boxes were consolidated into to one (I swap hard drives as needed and they just work(tm)). I want to make further cuts.

The physical systems in question all run windows xp sp3, and were old Pentium 4s with 256 MB of RAM. Currently, I have got a VirtualBox running on another system. My intention is to migrate all services to that. We can assume that disk space and RAM on the host is not an issue.

I'd rather not go with a client-server physical-to-virtual (P2V) method like what VirtualBox uses now. I have a few specific concerns as well - specifically whether I'd need to reactivate or sysprep for dissimilar hardware first.

An offline tool for imaging (Windows or Linux) would not be an issue since the drives could be mounted onto another system I have anyway or I could use a LiveCD.

What would be my options for P2V conversion, and what would I need to keep in mind when doing this?