I found 2 very clever work-arounds on the Windows 7 Forum that would probably work with Vista and might just solve your problem, or at least be pretty close.
In regard to suggestion #1, there's another way to look at your problem that may be more helpful. For clarity, I would describe it this way: you can ADD your Photos folder to the Start Menu Right Pane, and DELETE the default Pictures folder. (I think this is what the OPs were alluding to. . .)
1.
Substitute an Added 'Default' Folder with Your Custom (Photos) Folder
Right click Start Menu, go to Properties, Start Menu, Customize and choose any listed default folder that you don’t already have in your Start Menu Right Pane. Opt to display that folder as a link or menu. Add that folder to the list, remove the default location, and add the location of your own Photos folder, selecting the "Include a folder" button.
Once it’s in the Start Menu Right Pane, right-click it and Rename it to Photos. (Then, if you wish, you can delete the default Pictures folder -- or leave it and have both Pictures and Photos in your menu.)
2.
Reset User Folder Option: Although you can't add custom folders to the right side of the Start Menu, you can however set your User folder to open as a menu instead of a link, and it will expand out and you can get to your custom Photos folder that way. One extra step but that's about all you can do.
Start Menu - Customize