how to stop a script to start xampp by default in a startup

i was wondering about how to start xampp in my ubuntu 13.04 just with a script, i end up with a script that will start xampp after i start my machine automatically. what i did is : sudo gedit /etc/init.d/lampp a lampp file open with gedit. then

#!/bin/bash
/opt/lampp/lampp start

paste it in lampp

to make it executable

sudo chmod +x /etc/init.d/lampp

run following command to install init scripts to all runlevel

sudo update-rc.d lampp defaults

i got success after i rebooted and xampp starts automatically but when rebooting a script is running in a black background which i think is initialising the xampp and starting it.

now i want to remove it as its forcing xampp to start with bootloader.so for that i opened lamp file again in gedit and removed the lines #!/bin/bash /opt/lampp/lampp start . my xampp is not starting after a reboot but the script is initialising with bootloader before login screen come. is there a way to rever that update command or stop it by default?

and also after that i am facing a serious screen resolution problem where my screen comes to type laptop and 640 reso before i was running in 1024*768 with 75hz . i have configured it with monitors.xml file located in home/config/monitors.xml i have updated my nvidia drivers with sudo apt-get install nvidia-current.and i could not configure nvidia drivers by typing gksu nvidia-xconfig its asking for admin password when i enter it exiting. the admin password i guess i am giving wrong putting my username password

thnks for the help in adv.