photoshop questions can i use this too do some fun pics?

Yes, photoshop can do all of this and a lot more. There are a tonne of tutorials out there to show you how to do this really professionally too so it actually looks real.

Here's one example of how to do it:

http://www.metacafe.com/watch/608891/changing_background_in_photoshop/

with photoshop can i cut myself out of portrait and say place me in paris or LA for example if not photo shop then what program