1. Your 2003 PowerPoint presentation can be viewed by your dad's PowerPoint 2007.
2. You can save the powerpoint 2007 as powerpoint 97-2003 format (.ppt). Click the Office button, point to the arrow next to Save As, and then click PowerPoint 97-2003 Presentation.The Save As dialog box appears.
In the File name box, enter a name for your presentation, or do nothing to accept the suggested file name.
In the Save in list, select the location that you want to save your presentation to, or do nothing to accept the suggested location.
Click Save.The file is saved as a PowerPoint 97-2003 Presentation (.ppt) file that you can open in PowerPoint 97 through 2003.
Note: if you use new features like 3D in powerpoint 2007, they will not display in powerpoint 2003 of your school.
To keep complete of your 2007 presentation with new effects, you can save it to video or DVD using a converter like Moyea PPT to DVD Burner, which can save everything from your original PowerPoint to a video or onto a portable DVD disc capable of cross-platform playback, including embedded audios and videos.
Downloadable at: http://www.dvd-ppt-slideshow.com/ppt_to_dvd/
Hope this a help to u!