I'm sorry, I initially used a recursive search and removed the /s while editing it because you hadn't mentioned if there were subdirectories, but Squashman's modification will work if all the files are in H:\ and the following modification should work too if there are no subdirectories - I put the /s back in.
dir h:\*.* /s /b /a-d |findstr /v /i /L ".mpg .mkv .mpg .mpeg .jpg .png .bmp .gif" >"%userprofile%\desktop\file.txt"
for /f "usebackq delims=" %a in ("%userprofile%\desktop\file.txt") do del "%a"