Try uninstalling and reinstalling using a different method by downloading the zip or 7zip version as outlined in these simple to follow instructions.viewtopic.php?p=179699#p179699
Make sure you have stopped any components and removed the ticks in the Svc check boxes and clicked on Exit in the control panel to close it or you may not be able to delete the xampp installation folder.
You must install to C:\ for example so you have C:\xampp not to C:\Program Files (X86)\xampp or your XAMPP components may fail.
Make sure you are virus and malware free as this may affect the installation.
XAMPP does not normally affect your PC in the manner you posted about but if your system is faulty then the installer may give issues and is why you should try the zip file method.