If there is no animation on any opf the Powerpoint slides, you’d be much better off saving them out as individual images.
To do this, go File – Save As and select an image format (jpg, png, etc.) in the Save As Type drop-down box.
Once you do this, you have the option to save only that slide or the entire presentation.
Be advised that you’ll have to renumber them as Powerpoint saves them as slide1, slide2,…slide10, etc.
If there are less than 100, rename the first 9 to slide01, slideo2, etc.
If there are more than 100, you’ll have to go slide001, slide002, slide010, slide 011, etc.
This is so that they will be in the right order when you import them into Vegas.