Really, you shouldn't have your crm/sql installed on a domain controller, and crm requires a domain controller.
however my dev env (like yours) is all in one.
Work has given me a copy of VMware workstation.
which is really handy with the snapshots etc, also I am able to install crm 2011, windows, sql etc just by hooking up a copy of a pre-built image I made.
an alternative, if you want to upgrade to windows 8, you can use hyper-v, some of the features are a bit lacking compared to VMware at the moment (IE: usb flash drives are a pain in the ... on hyper-v), but the features you will really be wanting are there.,
long story short, crm requires one of the "server" windows installations.
you could always dual boot?
Good luck, if you have any questions let me know.
Regards,
Mark Spiers