How can you work with a particular method that is available through WMI, for example.

Under the WMI tree of /root/default:StdRegProv is available, and it has methods such as GetBinaryValue.  In my case, the value i need would be under HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion as Data under "DigitalProductId". How would you be able to construct a query using the WMIQuery feature in this type of situation ?

Secondary question is, would it be possible gather all variables under a particular set of data as oppose to being very picky and input the variable name?  In other words, as with sql queries, why can't i just say WMIQuery(/root/CIMv2,SELECT * from Win32_UserAccount) and parse data accordingly, as oppose to WMIQuery(/root/CIMv2,SELECT * from Win32_UserAccount, Name).  Is there an operator such as "ALL" or "*" for the the substitution of the NAME that can be used to a similar effect ?

I apologize if I am asking something that may be inherent in documentation but I haven't been able to locate it thus I figured I ask here.

Thanks
Samy