Wow, that is significantly longer than the reported <50 seconds from systemd analyze blame command.
I think anyone would be unhappy with a near three minute boot.
I believe you are asking if you reinstall Zorin OS, will your files be lost.
Yes.
What I do is I backup my Home Files that I wish to keep in an external drive. If doing this all at once, it can be a time consuming project. For me personally, at least, this was one of those hard learned lessons: To do regular back ups in small and quick bites, rather than to do larger ones further apart. Some use a Cloud Storage drive - which is the best way.
Only you know currently how large your home directory is and where you can backup to.
Once backed up - your home files will not be lost. They will need to be moved over to the new fresh install.
Sometimes, a Fresh Reinstall is just the thing to get problems sorted out. And it often results in some healthy cleaning, too (I know my downloads folder can accumulate a lot of clutter.)
Looking at your fstab file above, your current partitioning is fine.
Some may recommend that you create a New Partition for your Home directory, though. What this can do is isolate your Home Directory so that if you must reinstall, you are less concerned about losing files in Home.
As long as you allow at least 100gigs for root and the rest for home, that should also be fine.
I will admit, I do not practice this, though. I get the idea... But it has been often enough that while trying to help other members troubleshoot issues on this forum that we discover that the files causing the problem are actually located in the Home Directory.
And as I pointed out above, the Home Directory accumulates a lot of clutter.
So, I prefer a fresh start with Home Directory as well.
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