Computer not booting from drives

Hello,

My first problem is I cannot open Internet Explorer from my desktop [getting an error message saying, cannot find iexplorer exe. file] that is when I tried to re-install my windows xp operating cd after trying other things. I tried changing the BIOS configuration to boot from IDE drives but i'm keep getting a reading [press F1 or F2] it will only boot if the hard drive is added, it will not boot from cd or dvd drive first. Please help anyone.