Thanks in advance for taking a look at this thread

I'm running a Dell e1505 Laptop with dual-boot Ubuntu and vista. After reinstalling vista, I had to reconfigure grub. However, this killed my ability to boot. After the initial Dell boot screen comes up, it goes to a black screen with the blinking dash in the top left corner...and that's all! :/ I've tried to boot a vista repair disc and ubuntu live cd but neither of these cd-roms can be booted and once again the system goes to the black screen. I even tried changing the boot order in the BIOS menu but that leads to the same dismal fate. I'm stumped! Does anyone know what the problem might be and if there's a solution? Thanks.