[I_Still_Know!]

The first one to me sounds like 'Critters' to me.

As mentioned above it has been a while since I have seen it, but I am pretty sure they are in a barn at one point of the movie. And there were several Critters after the humans which fits your description.

Can you remember spikes being shot at people from the creatures at all? They do that.

I don't what yeti's look like, so I can't comment on any similarity between the two.