Whenever you restart a SpectroSERVER, the counters are set to 0. There are a lot of performance type attributes which always reset to 0 when the Spectrum server starts.
I'm not sure how Traps Ignored relate to Traps Discarded.
I would assume traps that have no destination (ie. no model with that IP) would be ignored and any problematic traps (i.e. traps which have an OID which Spectrum doesn't know about) will be discarded.
Not sure though - been trying to find out the difference between these two.