I'm getting ready to scrap an emachine desktop. what should I remove from the pc to be sure nothing is retrievable.

I had this same problem with my Emachines W3609 PC, it had the power on lights and nothing else. Try making sure that the hard drive and everything is connected properly inside. If the hard drive or RAM isn't connected it won't turn on. If that doesn't solve your problem than you might just need to get a new hard drive and re-install which ever Windows OS you want. Should work than.

be sure nothing on you keyboard or pressing any key

Ensure that all required screws have been removed. Make sure that you're removing the correct panel. Clear any cabling that make be hanging up your removal of the panel.

Possibly a power supply. Be sure to check all electric cords, etc. first.

chang computer power supply

the power supply. Go on craigs list get your self a 350 watt power supply u can get them for 10-30$ I my self have found them there for 10$ replace the power supply. Can you handle that?

remove the processor,ram for 30min and put them back

Make sure the RAM is seated, the CPU, any video card and the Power supply is properly connected.

If you power it on, still get no POST (beep at startup from the PC speakers) its time to replace the motherboard.

Cause you have Spyware in you'r system. Use a Ad-Aware 2007 to remove spywares from u'r computer, restart and ready to go!

Do a search on your XP machine for autoexec and then right click in the bar that says "Name, Size etc. and make sure to select "type". You will see that the autoexec is of type "NT" and not type bat. then try again.