I'll admit that some of my tutes could be updated but installing addons to FSX is basically no different from earlier versions of the MSFS series. The same applies to Windows XP. The
Windows Classic interface is much the same in all versions of Windows & changing a few settings from Windows Explorer Folder Options makes things a lot easier. Please read my Windows Basics & Working with Windows articles from the link to my Lair in my sig.
PS. I like to keep things as uncomplicated as I can & it's not possible to cover everything in a basic tute. Once you understand the basic principles it gets much easier. If there's anything you don't understand ask on this forum or contact me direct. I cannot support FSX or Windows Vista as I have no knowledge of them myself.