The answers are in the details.
What version of Premiere Elements are you using and on what computer operating system is it running?
Lots of ways to achieve what you want. Generalizing, have you looked at Premiere Elements Effects Mask with Blur Effect?
Use of rack Matte for blurring face is frequently a choice, but Effects Mask should be quicker.
Elements 12. Windows XP SP3.
I'm new to making videoclips using computer, I will follow the link you posted.
there is part teaching how to blur a robot head. I will take serious look to that example, thanks a lot..
In ATR's Reply, above, a letter was missing - he was referring to the Track Matte Keying Effect.
In addition, this article goes into some detail on the process, but it's focus was on "Highlighting" a subject, rather than "Masking" part of it. Still, the process is the exact same, and one could use any number of Effects on the Duplicate Clip, such as a heavy Blur, or Mosaic. One would just decide which Effect is more aesthetically pleasing. http://forums.adobe.com/message/1765005#1765005
One can use any number of other techniques, such as the "black bar" over the eyes, or even a smilie over the subject's face. This article discusses using a Shape, or a Character over Video: http://forums.adobe.com/message/3702803#3702803
Following the subject, to keep the Effect, Shape or Character in position, with Keyframing of the Effect>Motion>Position will be the same - the actual Shape, or Character, will differ, per one's desires.
Good luck, and if you have any questions, please do not hesitate to ask for clarification.
Thanks for taking a look at the suggestions.
Please do not hesitate to ask if you need clarification on anything written.
It looks like my typing fingers "slipped" in post numbered 1 of this thread. But, Hunt caught it.
Yes, I was referring to Track Matte, no such thing as rack Matte.
Best wishes for the day and always,