Here is a list of the most essential Windows Desktop Software. It is list of free/free for personal use software and will be updated regularly.
CCleaner by Piriform.
The one stop solution to clean up Windows PC. Cleans up junk files and built in tools help in a few Windows tasks.
A light weight photo editor packed with tons of features. It covers all requirements as far as image editing is concerned. Cant compare it with the pros, but does its job well. Free and no ads.
Download Link and Home Page