Operating System CD and Drivers and Utilities CD

I have a laptop Inspiron 1150.  I installed a new hard drive, plus increased memory, but then I could not find my file that contained the CDs for the Operating System and the Drivers and Utilities CD to reinstall them on my laptop.  Dell support said they did not have Windows XP CDs that I could purchase.  I would have to buy a Windows Vista, $255.00.  I have both CDs that came with my desktop.  They said I could not use them as each computer had their own.  I am a new novice computer person.

What could be my solution besides purchasing the Windows Vists complete system? After buying the hard drive and more memory, and then if I have to purchase Windows Vista,  adding all those costs up I might as well send the other parts back and just buy another computer.

Any solution?