I have a Dell Studio 1555 I didnt remember the password so I tried to reinstall the OS, however I used the wrong disk. It belonged to an older computer. Now the laptop has two OS systems installed and it wont boot. It will load to the MS screen and will not go to the windows login screen. Is there anything I can do manually to remove the system? I dont have a back-up disk, or driver disk. I can get the command prompt from the older OS disk if that is helpful.