At the beginning of the movie, Tommy and his young friends are in the jungle when they encounter a ferocious looking tiger that chases and bites at them. They eventually elude it, but then encounter an initially menacing-looking crocodile. They then end up sinking in some mud, but all of that turns out to have been the imagination of one/all of them as Angelica tells a story of such adventures and dangers (in the backyard).
One of the bigger scenes of the movie is when the Rugrats characters encounter a large storm that causes them to abandon ship. This scene might be suspenseful for some younger viewers.