Cannot install The Sims 3 on Windows 7 ulitmate 64 bit

I've checked the forums here at Windows seven forums and still have not found my answer. I recently received a Dell Inspiron 1545 with Windows 7 Ultimate 64 bit. I put the disc for The Sims 3 in the disc drive, but the download box won't open. I've opened Run, but my computer will not recognize the disc. I've updated my DirectX player via the suggestion in another thread. I know the problem is not the disc, because my friend tried the disc in their laptop for good measure, and it installed for them. Any suggestions on what I could do?

Thanks

--DPic75

probably really silly question but is the drive your putting the disk in a c.d drive or dvd?