Photo Editing:
Adobe Photoshop is the best photo editing software out there. Another cool thing about photoshop, is that is that it works quite well under WINE, so you can ditch The Gimp. The Pricetag for Photoshop can be a bit hefty if you don't use your rescources to find it on the cheap.
Video Editing:
Apple makes iMovie (Still, I think) which is pretty cheap. (Free. I think) . Prices go rapidly up from there. Final Cut Pro, (Apple, again, available for Windows and Mac) as well as Adobe Final Cut, and Avid XPress Pro are pretty much industry standard, and can cost some SERIOUS Cash. On the other hand, Avid has a Free Version of their software here:
http://www.avid.com/freedv/resources.asp
If you're running Linux/Un*x Avid *Might* work under WINE, but don't take my word on it. A free Video Editiing system for Linux is Cinelarra, but the Minimum Hardware requirements for it are REAL steep. (IE , dualheaded AMD 64, not to mention a Rendering Cluster.)