I was going too say I would see all the amazing natural and historic areas on earth that i didn't get to while alive. After reading your comment, i realize it's the only right answer
Haunt some of the powerful but evil people in the world and see what I can change. Let's see how effective a dictator like Kim Jong Il can be with a ghost all up in their business.
If I have poltergeist abilities then I suppose just straight up assassinating people would be possible. After all, if you can shove a book off the shelf or flip a light switch then breaking a few tiny blood vessels in someone's brain to give them a stroke is going to be easy. Not that killing other people would be easy, but maybe as a ghost I'd have a different perspective on death.
Let's suppose basic ghostly/poltergeist capacities, so nothing on the level of a great spirit or deity, in which case basically yes to what you mention (and in similar ways, so the whole hearing/seeing would be something you could flip on/off, make a case by case to mess with folks, etc.).
Spend the first hours exploring my limits.. how high can I float, how fast, walk through walls etc.
Then go places I shouldn't be.. listen in on stuff. With all the UFO/alien stuff lately I'd go to Area51 and snoop around.
Since I presumably can't play video games anymore without hands, I'd probably watch others play games over their shoulder and judge them for not playing the same way I would. If they made a really bad misplay I'd probably turn into a poltergeist and start throwing stuff
Interesting. I absolutely would horrify people. Especially children. Like ruining their sleep. Mess with them until they are admitted to the funny farm. Grow a habit out of that and do that over and over again, in different areas of the world until I become a legend of a nightmare that actually comes true.