Operating System: Windows 7 64-bit, using Classic Shell to display classic Start Menu.

I finally figured out the solution to the following problem, so I'm putting it here in case it's been bothering anybody else:

One quick way to jump through the Start Menu programs is to press the key corresponding to the first letter of an item on the programs submenu. For several years now, the folder named "Spybot - Search & Destroy 2" has not responded to the S key; pressing S skips past it to the next "S" item. I could rename it to start with any letter and it still wouldn't ever be selected pressing the key corresponding with its first letter. Super annoying, especially if it decides to respond to some other key.

I just now figured out that if I remove the "&" this incorrect behavior goes away. I'm guessing the menu was trying to interpret the the character following the ampersand as a hot key, similar to how program menus Windows forms do. (E.g., when your Windows program menu displays "File" and "Exit" it's actually using text stored as "&File" and "E&xit".)