Or you could use the little camera icon on Project's Standard toolbar.
Here's what I do:
1. View | Gantt
2. Display the columns I want to see (usually ID, Name, Start, Finish) and the Gantt chart I want to see (setting the Timescale, for example, to something appropriate).
3. Click on the Name field of the first task I want on my PPT presentation.
4. Hold the shift key down and press the down arrow to select the tasks I want in the PPT slide. You can get about 30 tasks on a slide (depending on a variety of factors).
5. Click on the camera icon
6. Switch to PPT and paste.
7. RightMouseButton on the graphic and set the size and location as appropriate.
If you've got lots of predecessor/successor links you'll see that the PPT slide only shows links to tasks that are on the same slide.