For each of the applications, open up the app, click the menu button (four lines) at the bottom of the screen. Go to more or settings (or whatever choice they give you) and you can change your notifications in there.
To delete applications that you have downloaded, click the menu button, click settings, click applications, click manage applications. Find the one in the list that you want to delete and click on it. A screen will come up giving you an option to uninstall.