First an old trick. Duplicate that original Dell boot disk and try the duplicate ONE LAST TIME. Clean the CD/DVD lens and the very last try.
If that fails and you are sure it's set to boot from that drive, try a new CD/DVD drive.
I am using a Dell Inspiron 2650 with WIN XP SVPK3. Computer will not boot from my Boot Disc or from original Dell boot disk. I cannot boot in safe mode or any other mode from f8. I have removed hard drive and installed it in an external enclosure. I have been able to copy and save all my data. I can access files but cannot figure out how to repair. The download programs I have tried will clean or repair my main working computer but I can not figure out how to clean or repair WIN XP on the external drive. I would like to repair this issue and continue to use this computer.
Thank you, Microb