Ive tried every way i know to reset my factory settings (i.e F10 at boot screen but it doesn't register that i've pressed it, and i also dont have a start menu or any icons because when i start the pc it just comes up with my screensaver) i have to run any programs via ctrl+alt+del new task and i have no windows disk as its all built in can anyone please help thankyou

make sure you keep F10 pressed as soon as u switch the PC on, you might be pressing it too late. I'm not familiar with the F10 method for doing a factory reset/recovery. usually you either get a CD to boot from, or you get a floppy-disk to boot from which then starts a recovery menu. Sure you didn't get a floppy for recovery?