Remove Properties and Personal Information - Batch mode or app

You will need separate tools for different types of files, to gain the control you seek.

To batch remove image EXIF metadata, use Irfanview (and more here)

To batch remove MP3 metadata, use The GodFather. Although I'm not too sure why you'd want to remove your ID3 tags?

MP4's can contain anything from lyrics to album art, but I'm sure it won't contain any personal info, unless you put it in there specifically.

Update: To blank with TGF, scan the songs you want to clear, onthe Tag tab (green) check all the fields to blank (red) and click the Apply button, then click Update.

Go to your Music Library. Click the dropdown labeled "Arrange By" at the upper right. Choose "arrange by song".

You will now have a listing of every song in your music library. Select all those you wish to remove the properties from; then right-click and choose properties. Go to the details tab and click "remove personal info". Voila!

Make sure to change your "view" setting back to "folder" when you're done, otherwise you'll have a hard time sorting through all your music.

For JPEG images, my favourite tool is EXIFCleaner by Superutils.

ExifCleaner is a batch Windows utility that lets you to remove individual Exif tags or to strip Exif data entirely. This protects your privacy, helps you to hide unneeded or sometimes sensitive information -- about the image, photographer and location.

It's free for 30 days, but works like a charm even after the trial period ends.