simplest way is to make a batch file botname.bat, and fill it like so;

cd c:\path_to\bebot
c:\path_to\php.exe startbot.php botname
and a set of botname.bebot.conf/botname.mysql.conf

make a shortcut to this batch file in your Start -> Programs -> Startup... repeat for each bot... now they start at login

or you can add the same info to the registry local machine 'run' menu, and it will start before login