Press and hold any of the apps and after a couple of seconds or so they should start to shake. Then press the 'x' in the left corner to delete the ones that you don't want, and when you've finished deleting press the home button so as to stop the shaking. If you don't get the 'x' on any of the apps that you've downloaded (you can't delete built-in apps) then check that Settings > General > Restrictions > Deleting Apps isn't set 'off'
press down on the unwanted app until it starts shaking
then a x should appear in the top left corner
press on the x to delete the app
(it will come up with a notice if you are sure you want to delete the app,)
and it will have deleted the app
if you just want to move just press and drag it to your desired destination
to resume to normal press the home button