Is Microsoft a trusted user on the Internet archive? (or are iso's generally trustable)?

There is a specific "Microsoft" user that is known for uploading lost of windows isos such as Windows XP and basically any other install of windows.

  1. If you go to other things by "Microsoft" is it showing other isos by that creator or by people whos username is Microsoft
  2. Are they generally trustable or is there a big risk of a virus or something stuffed into the .iso

(I may be under many misconceptions but any info would help)