Sounds like the boot sequence is set to boot from cdrom and not the hard drive.
Restart (or turn on) laptop.
Press F11 as soon as it starts up (before the beep). This should take you to the bios menu.
Look for "boot"order or something similar (not entire sure what HP's exact words are).
Enter that menu and you should see 2 options (maybe 3 but probably not).
Option 2 (you probably won't see option 1) is CDROM
Option 3 is hard drive or notebook hard drive.
Set option 2 to the hard drive (hdd) or notebook hard drive by either pressing the right arrow key, or enter.
Setp option 3 to CDROM
Reboot. If after a couple of days you stop having issues you should be good to go
If you have issues still (you might have a corrupt master boot record "MBR") and have the windows cd follow the steps below.
Insert the Windows Disc into CD (or DVD) drive.
Turn off the laptop.
Turn on the laptop.
Press the Enter key when prompted to Boot from CD .
From the Windows Setup Menu, press the R key to start the Recovery Console.
At the C:\> prompt type FIXMBR then press the Enter key to continue.
Press the y key then press Enter when asked if you want to write a new MBR.
Once it's done restart the laptop.