Engines comparable to source:
crytek
udk
unity
(doom/quake/id tech)
Engines comparable to ogre:
irrlicht
Physicsengines
physix
bullet
The best choice for making a pretty standard game are one of the top engines: udk,crytek,unity (most with free license models available). When you want to play around with the sources , irrlicht is an alternative, but ogre nor irrlicht are up to the state of one of the major players.
An alternative is one of the open sources id-tech engines, I'm not up-to-date, but I think that atleast the doom3 engine is available (id tech 3?).