While the actual damage to the A/C does not appear to be "beyond repair" a landing with a prop disintegrating ("exploding" is a bit steep), a wingtip touching the ground and the A/C turning 90 degrees into the grass must feel quite disconcerting from the flightdeck, even if you anticipate it (at least it always does on the Sim).
There appear to be flames in the right engine area after touchdown although they're gone by the time the fire truck arrives.
With damage like that I'd rather think "evacuate" than keep everyone on board with a risk of fire. There is no way to assess the whole situation from the flight deck and getting pax out seems to be the safer option to me.
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While pilots are instructed to shut up after any mishap and usually do so, it is interesting to read how there's always someone willing to make unwarranted statements, in this case the chief of the Airport's fire department. Unless I make wrong conclusions from the Danish reports, he comments on how a foam carpet would have reduced the risk of fire on touchdown (although we have been taught for years that foam carpets are not such a good idea) and that it was seconds/millimeters from a full-blown catastrophe (how very reassuring to pax).
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AFAIK the landing gear on the Q400 is similar in design and operation to the one on the Q300 but much beefier. Interestingly the Dash 8-100 had problems with "gear bumping" (i.e. gear falling onto the gear doors without apparent reason) later attributed to proximity switch problems in it's infancy (i.e. the mid-eighties). These were later resolved.
The Q400 seems to have had more than it's fair share of "infant illness". One sometimes has the impression that Bombardier was too eager to re-invent the wheel. Otherwise it is hard to understand that such basic things as gear, doors, rear airstair malfunctioned quite a lot. (I can't compare however. Reportedly early Airbuses weren't without fault either.) Systems-wise the Q400 is quite different from the Q300 and more of a new A/C. (While pilots only need 3 days plus some SIM for the transition as everything is designed to look/work similar to the Q300, mechanics need a couple of weeks as everything is differnt under the hood.)