If I have to pick one application that I couldn't live without it would be PaneKiller.
www.maddogsw.com Hasn't been updated in four years yet still works flawlessly with XP. I'd like to see it updated and sent the author a few suggestions but never heard back from him. I'm surprised there are no other programs like this other than Stardock stuff. I guess I'll eventually replace the startmenu with ObjectDock anyway...
# Integrates into the Windows shell
# As easy to use as the Start Menu, but more flexible, powerful and configurable
# Access any file (application or document) on your computer, easily, from the taskbar
# If you prefer PaneKiller's power and flexibility over the Start menu, you can even replace the Start menu with PaneKiller.
# Drag and drop lets you manage files from within PaneKiller
# Tear-off menus give you handy access to oft-used items
# Fully configurable -- provide convenient access to as much or as little as you like
# Recent Files and Recent Folders features make your work easier by remembering items you've used recently, and making it easy to get to them
# Menus that are too long to fit on one screen give you a choice -- you can split them into several screen-sized pages, or you can scroll through them (using the mouse wheel if you have one)
# Customizable menu backgrounds let you determine the look of your computer
# Menu transition effects show off your computer's graphical abilities, are pretty, and are fun!
# In addition to opening files, you can also right-click to access context menus
# 32-bit, multithreaded for speed and stability
# One-click access to anything on your computer
# Hide icons on Windows desktop and access everything via PaneKiller, if you don't like clutter
# Fully accessible from the keyboard or with the mouse
