well i am new to dark hersy and my group has just started and i would like to know is it better to have just a combat group or a alround group eg shooter , killer , smart/Phyic

Depends on the game your GM runs. The published adventures tend toward a mix of investigation, combat and, on occasion, fleeing like scared children. A mix of specialities is definitely a plus, unless your GM is explicit about running a combat focused game.

Snidesworth said:

What career is best suited for "fleeing like scared children?"

The ones that get Sprint early on. And have less scruples about not dying valiantly for the Emperor. A quick glance at the talent tables tells me that this means the Adept is the prime career for running away, arms in the air and shrieking in terror.

So there you have it: if you want to make sure your Inquisitor hears of how the rest of cell died horribly make sure you've got an Adept on board.