Question before getting Win 10

I have a few questions before I get Windows 10. I did ask these questions on the Microsoft forums but I got FAQ Answers and I wasn't satisfied with the information I was given. I'd like information from someone who already has upgraded to Win 10 therefore the information is more based on personal use.

1. When I bought my computer it came with a 250gb SSD and I went ahead and installed an internal 1TB HDD and named it storage. I have a bunch of stuff on there from 10+ years, pictures, movies etc. When I upgrade to Win 10 is it going to clean or re-format this drive? Do I have to be concerned about it? Not only do I use it as storage I also have a few programs installed on there as well.

2. After I upgrade to Win 10 am I going to have to reinstall any programs or software? The reason I ask is because years ago I was attempting to factory reset my computer but I did a restore or reinstall and it basically installed windows over top itself yet none of my programs worked even though the icons were still on the desktop.

3. Some people were saying this version of Windows 10 has been slowing theirs computer down because of something called bit torrent? They are saying something about holes in privacy and security and information is being passed and shared threw the internet connection in the background and it's constantly running and making the data usage numbers to sky rocket. What are they talking about? Is this true? And how to can you put a stop to this?

4. How is the bubbles screensaver in Win 10? lol

The upgrade process should keep all of data and all compatible applications. You should still do a backup of your data in case something goes wrong with the upgrade process. You might have an application that isn't compatible with Windows 10, so you'll want to check on that. Make sure you uninstall any 3rd party anti-virus software before you do the upgrade.

Windows 10 has a new feature that speeds up getting updates by allowing it to share updates you've gotten with other users running Windows 10. You can restrict this to your local network so it will only share updates with your own computers. You can also turn off this feature completely. You can change this under Settings-->Windows Update-->Advanced Options-->Choose How Updates Are Delivered.

1. It will not touch that storage drive.
2. It depends on how you install Windows 10. If you upgrade, all of your programs will be in place.
3.It has made my computer faster.
4. I do not know, never head of bubbles.

1. You are fine, it won't touch any of your files (as stated above)
2. It most instances all applications will run just fine, it will tell you when it does a check before you upgrade if anything will not function.
3. It will seem very slow at first (I have updated 3 of my computers now, 1 with very high specs from win 8.1 pro the other 2 very low, one 7 pro, one 8.1 home on a tablet), Windows needed to update new graphic drivers on all 3...just let it do what it needs to do and then all of them were as fast if not faster than before. You will be fine...just be patient.
4. Windows Updates in Windows 10 now function similar to a P2P (pier to pier) way of sharing. You can turn this off in the advanced settings of Windows updates.
5. Bubbles look the same...see below

@rjkolo As for the bubbles screensaver on Win 8.1 if you preview it looks like your picture above but if you actually set it as your screensaver the bubbles actually appear over a blank colored background instead of over the desktop.
When you set the bubbles screensaver and it activates on it's own is it over a colored background or actually over the desktop?