After a lot of googling this morning I was able to find out how to determine the version of the Windows ISO file. This was important to me because I needed to know if the ISO I had included SP1 or not. This should work for Vista and up, basically any windows that has WIM files within.
First you will need to mount the ISO file to a computer so you can browse it. Then open up a command prompt as administrator and run the following command.
dism /Get-WimInfo /WimFile:E:\sources\install.wim /index:1
(E is the drive letter for the mounted ISO file)
Here is an example of the output from the command for a Windows 7 Enterprise ISO without any service packs.
C:\WINDOWS\system32>dism /Get-WimInfo /WimFile:E:\sources\install.wim /index:1 Deployment Image Servicing and Management tool Version: 6.1.7600.16385 Details for image : E:\sources\install.wim Index : 1 Name : Windows 7 ENTERPRISE Description : Windows 7 ENTERPRISE Size : 11,912,905,130 bytes Architecture : x64 Hal : acpiapic Version : 6.1.7600 ServicePack Build : 16385 ServicePack Level : 0 Edition : Enterprise Installation : Client ProductType : WinNT ProductSuite : Terminal Server System Root : WINDOWS Directories : 13629 Files : 64547 Created : 7/14/2009 - 12:49:53 AM Modified : 7/14/2009 - 2:43:28 AM Languages : en-US (Default) The operation completed successfully. C:\WINDOWS\system32>