This is a guess, since I don't use windows. But if you can load Ubuntu and mount your directories then you're getting there. It's reasonable to expect that you might can get it back.
First look and see if there is anything in C:\xampp\mysql\data - if it isn't there you'll need to figure out where xampp was installed and get to that directory. Get into the mysql directory and locate the my.ini file. Open it and find the value of datadir - that's where your data is stored.
As for restoring those files once you copy them to a safe location that's a whole other animal.