video quality of web objects

Hi,

I have recorded a software demonstration with adobe captivate 5.0.

The published version has a very good quality.

When I import the video as web object to PowerPoint and publish it, the quality is not only bad, but on the screen I see line that don't exist. As on the two pictures below:

These are my Presentation Options:

How can I improve the output quality?

Thanks and regards, Florence