runnin

Help please, guys not sure what i've done ,but i was bootin my ibiza pd100 from standstill ,then there was a muted bang and puff of white smoke from exhaust. engine runnin erractic and white smoke from the exhaust now. smells a bit too of burning. im about quarter mile from home, should i risk...

right im about to fit my new engine in my car but am a bit unsure as to 'how to run it in' ive been told by a few people that ill need to give it quite a bit of beans while runnin it in but im not sure as and when i should be doin this, oil intervals etc i was assuming that i change the oil at...