This uses Choice
to provide the delay and an errorlevel to check, so that it will abort if C is pressed. It also provides an extra option to shutdown immediately.
Timeout doesn't provide an errorlevel on abort so pressing any key to abort doesn't seem to be an option.
@echo off
if exist "C:\Program Files (x86)\VideoLAN\VLC\vlc.exe" ("C:\Program Files (x86)\VideoLAN\VLC\vlc.exe" %1 %2 %3 %4 %5 %6 %7 %8 %9 %10 vlc://quit) else (goto :EOF)
choice /c CS /D S /T 120 /M "Waiting for 120 seconds: Press C to cancel shutdown, or S to shutdown now"
if errorlevel 2 shutdown -s