Is it a Korean language operating system? If not, you probably have to take ownership to delete them. If they are in use by the OS, you do not want to delete or you will have problems. In that case, you might try resetting fonts to default.
Start> In search box type fonts> Enter> Font settings on left> Restore default font settings
And/or run the System File Checker SFC /SCANNOW Command - System File Checker