+0

1."She went hiking yesterday. Unfortunately she fell to her death."

2."I have to climb onto the roof because my house is full of spiders."

Are they correct?

+1

These are correct English. (1) may seem a little casually phrased for such a tragedy, depending on context. (2) is a bit weird in terms of what it's saying, but the English is correct.

You have spacing error in the numbered points. The spacing should be like this:

1. "She went hiking yesterday. Unfortunately she fell to her death."
2. "I have to climb onto the roof because my house is full of spiders."

Comments  
Oaihan Schizerion1."She went hiking yesterday. Unfortunately she fell to her death."

A sentence adverb takes a comma: "Unfortunately, she fell to her death."