Assume that the future can change based on your actions, so any historical information that you bring along with you from the intervening 25 years may quickly drift out of the new realities history.
Edit: also assume that you can be given a healthy 21-year-old body if you want or take your previous self’s place.
Further, identification will be provided for you if you were not born at that time.
To take over the world? I’d take the records of every international technology and medical patent. And, a cell phone. I’d get the local news interested in my new handheld PC, find the least scrupulous tech company which reached out to me, and hatch a plan to create a trillion dollar tech empire.