I design and build electronic projects.
What is the best software out there that can simulate a circuit before actually building it.
And this should include pcb layout up to two or more layers..
Digital clocks are my favourite to deisgn..using logic gates and display drivers..

i have heared about different kinds of computer softwares for electronics simulation, such as EWB, PROTEUS, PROTELL, P SPICE and many more… but is there any electrical engineer out there who can help me and tell me which one i should start working with?

I am working full-time in an Electronics related field and at the same time studying for M.Sc. in Electronics through Distance Learning. Being a Distance Learner I have a very few practical classes on the basis of which to develop understanding about Electronics.
Can virtual training softwares like PSpice, SwitcherCAD, Tina Pro 6, etc. fill up the void?
Also suggest some more software packages for turning my PC into an Electronics Lab?