The same tools that I would use for any other software testing for the platform that the shrink wrap software runs on.
I know that Microsoft was using Compuware suite but I would expect that that is not their only tool.
The best way to choose a tool is to identify what you expect from it to do the testing that you plan to use it for.
Use an RFP to determine if Vendors can support them
Get the vendors who can support your requirements to do a demo
based on the Demo do a proof of concept on the own operating system and applications