Sewing Machine Froze Up

Question

I was threading the bobbin and suddenly my machine just slowed and froze up and I can't get it to move. I took it apart to see if I could see anything and tryed to take the bobbin gear out to see if there was thread jammed in the teeth but I couldn't figure out how to access the bottom s***w. Please Help!
Any suggestions as to how I might fix this at home instead of taking it somewhere?