When I helped someone to sell her laptop on internet I needed first to look at what applications were installed in this Windows 7. But, having this list in a file was not an easy task, therefore I searched on internet to get a way to do this.
Finally, I used at that moment the command line "wmic" which also allows you to export this list in few formats, always remember first to open your command line window and type the command as shown in the image.
As you can see it's very simple just don't forget to specify the destination path and the format you want your output file (the options are: HTML, Table, XML and more). Once you got your file open it and you will see something like this.
If you want to have this file in a more comfortable scheme just do what is said here and it will look like this.
Ready to be used.