Hyper-V 1.0: List of supported guest operating systems

The following list of guest operating systems are officially supported by Hyper-V 1.0:
 
x86
x86-64
2x vsmp
4x vsmp
Windows 2008 Server
Yes
Yes
Yes
Yes
Windows 2003 Server
Yes
Yes
Yes
No
Windows 2000 Server
Yes
No
No
No
SUSE Linux Server 10
Yes
Yes
No
No
Windows Vista
Yes
Yes
Yes
No
Windows XP
Yes
Yes
Yes
No

Note that only specific Service Pack levels are supported on windows guests. Please refer to the link above for details.