Talked to tech support (son). I think we're gonna order some parts and have him install 'em. BTW got the front off and applied pressure directly to the on/off "button". No change in results .... Hard drive, (new) power supply, DVD are good. I think we'll order a new switch and mother board. Then again, I may change my mind in 10 minutes.
Probably wouldn't worry about the switch given what you're describing. Regarding the mobo, if your son is local and can do it in a timely fashion, sounds like a good plan. This country as a whole is pretty quick to throw the baby out with the bathwater, but it sounds like you've got a number of components still getting it done.
My only other possible thought on this would be to rule out CPU over heat (blow out the heatsink with compressed air) and electrical shorts from external connectors. To test the latter, remove everything from USB ports, printers, etc., and start it with nothing but the power cord and video cable connected.
Your son can likely do a little more testing, such as reseating the CPU, disconnecting HDD and CDRom, mobo connector pins (for speakers, power switch, etc), going to one stick of RAM, etc. The idea being remove as many components from the mix as possible in an attempt to figure out if it will start period. If you can, you add things one at a time until you find the thing breaking it.
Ultimately though, you're talking MoBo or CPU. Definitely worth spending the cash for compressed air (cheap) and blowing it all out.