How to create a Windows Shell Right Click command to easily add your WSP to the Solution Store.
Open regedit.exe and then make following changes in registry
Right Click on "HKEY_CLASSES_ROOT" and create a New Key called ".wsp" and set the value to "wspfile"
Right Click on HKEY_CLASSES_ROOT\wspfile and create a New Key called "shell"
Right Click on HKEY_CLASSES_ROOT\wspfile\shell and create a New Key called "Add Solution"
Right Click on HKEY_CLASSES_ROOT\wspfile\shell\Add Solution and create a New Key called "command" and set the value to "C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\BIN\stsadm.exe" -o addsolution -filename "%1"
Note in all the above values, make sure you remove the first and last inverted commas on values
Now go back and open Windows Explorer and locate your WSP file on your file system. Right Click on that file with your mouse and EUREKA you will find "Add Solution" as a new Windows Shell command. Select this option to add the WSP to the MOSS Solution Store