$windows~BT & $windows~WS

Good evening to all.
Hope I chose the correct section to ask this question as I wasn't sure where to ask.
I have a windows 7home premium Desktop.
Decided to have a clean up.On my C drive I only have the operating system program files etc,All documents pictures etc are on a second internal HDD.
Well upon looking at the C drive I notice that there were two folders one called $windows~BT and the one below is called $windows~WS.
Can someone please tell me what they are and is it okay to delete them or what should I do?.
Total amount in the $windows~BT is 5GB.

What's the best option Please what to di with those two folders.Been looking on the famous google and some say delete then other options that I don't quite understand..

$windows~BT & $windows~WS

Many Thanks.Awaiting help Please.

Hi,
They are related to the windows 10 upgrade,
If you don't want to upgrade see this,
But I wouldn't delete them until you remove the other associated updates/ cancel win-10 reservation.... otherwise m$ might send the 5gb folders back to you ?
Please help me get rid of the Windows 10 upgrade

Many thanks for the info.
But what would be the best way to delete it.

Thanks.