Before you start to edit the footage you need to acknowledge that you will need to have a powerful Mac because you will be working with large data files and you will need much processing power. On the other hands you could try: Adobe Premiere Pro CS 5 if you work with video footage or Adobe Photoshop CS5 in case you handle RAW image files. I recommend these tools because they have a good reputation among video editing and photo manipulation.
If you have trouble understanding how these applications work, you can always search for tutorials because there are plenty of them on the web.
