The repartition ***HAS*** effected Win XP negatively.
I don't think so.
[Aside: "effected" and "affected" are different words, with different meanings. No matter, I think I understand you
XP is inherently unstable. I have to use it at work.
Linux installations do not touch windows partitions, why should they bother?
The linux developers do not care if you wish to run windows, many of them do run windows as well, and then make it easy for you to do this with "dual booting".
There is no mischief involved. If windows isn't working, then please call MS Support. Back in '98 I tried this, but never, ever, got through to a real person, so I gave up.
Linux "voluntary tech support", as here on LQ, outsmarts and answers faster than MS "tech support" most of the time.
If you say to MS (if you ever get through) "XP was OK until I installed linux", they'll blame it on that.
They would, wouldn't they?
Now, back to your Q:
I have not used "Mint", but there's probably a button to click that says "Authorise", or "Make changes".
Then you'll have to give your password.
You'll learn to work in a different (IMHO "better" way) if you persevere with linux.
You didn't learn windows in a day, why should this be different for linux?