i love altium, personal favourite, its all about your personal preference.. altium can do a lot.. including programming of FPGAs and C and many other languages.. but like i say, its up to you, but Designspark isn't bad. free too i believe...
I know that Lockheed Martin and BAE Systems both use Mentor Graphics for schematic capture and layout. Engineering uses Pspice, Test engineering is into NI Test Stand, LabView, and CVI and C#