2000 Kia Sephia My husband is an idiot and my car is broken

Engine Performance problem
2000 Kia Sephia 4 cyl Manual 100000 miles

My husband and I have recently been out of a vehicle, due to the fact that it began bogging down. It started to squeal every time you pushed on the gas, and would only hit 40 MPH on the freeway. When going up a hill, it would almost (but not quite) die. Usually uphill I can go 5-10 MPH. We live in a valley, so this does not work for us. I know a little about cars, and my husband is a self-proclaimed genius, and has tore the vehicle up and now we are at a loss of what to do. We checked all the belts, and they were fine. The spark plugs needed to be changed, but it did not stop the lack of power, so we kept looking. I work at a towing company, and our mechanic does NOT know what he is doing. He suggested to look at the catalytic convertor, and so my husband took it out, and decides that the honey comb needs to be hollowed out. (The catalytic convertor was apparantly the cause of the whining, however, now it is dead). I need to find out what is wrong with the car before my husband gets the great idea that the transmission needs to be beaten with a metal rod next. PLEASE HELP! I can't afford all these parts!