|F10 is only for compaq. The correct key is probably DEL but may also be F1.|
Once you get it figured out you may need to 'enable the setup prompt' (or words to that affect). You may also want to enable the diagnostic scree so it shows the memory scan, drive detection, etc. instead of the emachine logo. The correct key should show then.
Real men don't use AntiVirus; they just reformat