Make windows fast again after long use

After a long use of Windows, a time comes when everything gets so slow. Nothing starts promptly and things start to get annoying. This usually happens due to continuous install and uninstall of software. Most users at this point usually consider formatting their hard drive just to make things faster. But may be users could try to make windows fast again by giving a little more time to make sure not to lose personal application settings.

Some users try defragmenting their drives. Still things are quite the same.

Actually, slowness of computers depends on several factors
-> invalid items in the registry.
-> expansion of the registry
-> too many unnecessary programs and services running

I consider registry compacting as well as cleaning software to boost up the registry.
Also remove unnecessary startup items from 'msconfig.exe'. Disable unnecessary services that are running in the hidden. This may look simple, but definitely helps a lot to make windows fast.

I personally prefer 'Super Utilities 7.69', a gem. It does everything for me. It clears invalid registry entries, cleans up disk by searching for temporary files, and many more.
One thing it lacks is registry defragmenter. But you can easily find such software for free on the net.
It also has got application locker, folder lock, process manager, service manager, RAM booster, and many more. It definitely helps to make windows fast again.