Aspire 5710 want to reset it as its crashed and need to format the disk to put windos xp on

During the boot process you will see on the screen to press a certain key to enter setup usually the Delete or the F2 key

Press and hold that key during the boot up process to enter BIOS the using arrow key scroll down to advanced bios features press enter change your first boot device to cd,press escape then press f10 to save to cmos to restart

note this will erase you operating system you will have to have an operating system disk to load it onto you hard drive or create a partition to load another operating system

(note after you have loaded the operating system you should go back and change the first boot device to your failsafe or optimized defaults)
after windows has loaded

your computer will automatically restart it might restart 2 times one to finish the installation
the next will be because the operating system is loaded and will boot from your cd

during the boot process you will see on the screen to press a certain key to enter setup
Press and hold that key during the boot up process to enter BIOS using the arrow keys load

failsafe defaults or load optimized defaults press escape then press f10 to save to cmos to restart
otherwise it will keep booting from the cd /dvd drive

hope this helps