Run a batch file everytime a command prompt starts:
reg add "HKCU\Software\Microsoft\Command Processor" /v AutoRun /t REG_EXPAND_SZ /d x:\cmd_init.bat /f
To delete:
reg delete "HKCU\Software\Microsoft\Command Processor" /v AutoRun
Remove web searches in start menu:
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Search]
"BingSearchEnabled"=dword:00000000
"CortanaConsent"=dword:00000000
Set to 1 to reenable.