The Registry Editor REGEDIT.EXE can take command line parameters. You can put the registry entries in a text file with an extension .reg . Lets assume that you want to execute notepad.exe when the system boots up, you can put the following entries in a text file named startup.reg
In the command line, execute "regedit /s startup.reg ". The 's' switch will make the registry merge silent. Make sure that the file startup.reg is in the current directory of specify the full path name to the file startup.reg.