Screwed Myself. Please Help me.

Ok. So i Bought a New motherboard and installed it, Now, noone told me and i have never even heard that when you install a new motherboard that it Clears your hard drive. So i took the windows Vista anytime upgrade disc and installled Vista home basic on accident. i had Vista Home Premium originally and only had the Key Code for Home Premium. After i realized i installed a version i didnt have a key for, i tried to install Home Premium with the same disc, it wouldnt work. there were all kinds of errors and it would restore windows to the way it was when i first installed Home Basic. So it gave me a 30 day period to enter the Key Code for Home Basic which i used up. The point is that i cant afford to go out and buy a brand new version Of windows Home premium, also i dont even want to even if i had the Money because i already have the Key Code for Home Premium. So now my computer is Locked, after Booting and looks like windows loads it goes to a black screen with no icons no nothing. Just a window that says purchase the rights online now, or enter a valid key code. so my question is this. I bought a different computer like 3 years ago. it has Windows Xp on the hard drive, i have the Back up disc for it, but the disc says on it that it can only be used with an E Machines computer, I have the Key Code for the Windows version that is on the hard drive. So, Can i use the back up disc in my new comp and will it install Xp? Keep in mind that my computer is locked. Now there is another computer im the house that has Vista Home Premium like i did. Is there a a way i can just take the OS off his comp somehow and install it on my comp without it screwing with my brother in laws comp? Or does anyone have a different idea of what i can do? Please any feedback would be great. thanks in advance.

Danny.

How can i format the hard drive when windows is locked and i cant do anything? there isnt even a start button after windows has loaded . . Ctrl+Alt+Del doesnt even bring up a window . . its jusy a black screen with 1 window for the activation of Windows . .If i X out of the activation screen the comp shuts down . .

Boot from the Windows CD dude... you have the option to delete / recreate and format partitions. Don't do it from within Windows... in fact NEVER attempt to install Windows or Windows Upgrades from within Windows... always boot with the install CD.