FYI:
Using the VBS with the invoke method works fine on my XP SP3 test machines as well as the newer platforms so you don't really need to be testing for which platform within the UDF.
If someone has got W2K systems still in use they might as well use the old method.

If you think the above was hard, You should see what I needed to do to 'Un-Install fonts'!
With the issues I was having which caused the need for the scripts in the first place I had copies of Windows 7 with numerous copies of the same font installed as the 2K3 method royaly broke Windows and users had to keep going to the font source and manually re-installing.

NB: When you read the extended attributes of a file in XP it gives totally different lines of output than in other OS's, became unneccesarily complicated so in the end it was a matter of parsing the registry and extracting the font file names to compare against the baseline ...Takes a bit longer but ALL file versions and the registry could be pruned. Even then Windows 7 in my case would randomly fail to delete properly some of the registry entries...and even re-booted on occasion, NOT FUN