Re-installing won't help. In any case, no, the installation package does not include this updated script. You need to slow down and try to gain a better understanding of how your operating system works. If it took you "forever" to build your database, you should not be referring to backup as an "option." Sooner or later, your database will become corrupt, and you will not be able to fix it. If you don't have backup, all will be lost. But even backup won't help you if you don't even know where your data and backup files are stored. So...
Use Explorer's details view—so it actually provides some useful information about files and folders. Is the "Movies" folder your PVD installation directory, or is it something else? Do you see viddb.exe there? Navigate to Computer - Hard Drive - Program Files. Do you see a "Personal Video Database" folder there? If so, is viddb.exe there? Does the folder have "Plugins," "Scripts" and "Skins" sub-folders? Are your plugins, scripts and skins there, or only in your "Movies" folder? And—most importantly—where is your data file? Before you do anything else (using Explorer), you need to find that, and make a copy of it. Making a copy of your data file is actually easier, faster and more efficient way to create a backup than the backup feature in the program.