Windows 10 Questions About Upgrading: Win7 -> Win10

[icu222much]

I'm thinking of upgrading from Windows 7 to Windows 10, but I have a few questions regarding the process and result. Essentially, my questions revolve around if I should be expecting that all my settings, applications, and documents remain identical after the upgrade process? What sort of changes other then a change in the UI and other OS related ness should I be expecting?

1. Would I need to reinstall any of my applications? I have some older applications where I don't have the install (Adobe CS, older video games). These applications are located across different partitions (C is my main, D is for games, E is for other applications...).
2. Do my application settings (Photoshop, games) get carried over after upgrading?
3. What should i backup, and what will get replaced? I will be backing up My Documents, and fonts. Will my Windows 7 settings (desktop wallpaper, startup list, files in recycling bin...) get carried over to Windows 10?
4. I currently have 30GB free on my main partition. This partition has Windows and my most used applications. Will upgrading to Windows 10 replace the files inside my Windows 7 folder? Will the Windows 7 folder automatically get deleted? Will Windows 10 create a backup copy of my Windows 7 folder so I can revert if needed? If so, will it be using the space in my main partition?
5. What is the application compatibility for Windows 10 like? I think the oldest applications I have are from about 2008-ish. Will that be fine?

 

[Neemobeer]

All of your settings, applications and data will remain intact. I have 120 steam games on my computer and only one of them doesnt work in Windows 10 so I think you will be fine. I would also just backup your user profile just to be safe.

 

[Josephur]

But let's be clear some applications may break, Steam games are not a very good benchmark as they are all stored within Steam's data folder and nice and neatly packed up. More complicated applications and those that are used to interface special hardware with special drivers are more likely to break. In my opinion a fresh install is really the way to go with 10.

 

[Joe S]

Even with a clean install you may find some of the old software or hardware may not work.
Joe

 

[icu222much]

But let's be clear some applications may break, Steam games are not a very good benchmark as they are all stored within Steam's data folder and nice and neatly packed up. More complicated applications and those that are used to interface special hardware with special drivers are more likely to break. In my opinion a fresh install is really the way to go with 10.

How would I do a fresh install when performing the complimentary upgrade from Windows 7 to Windows 10?