We are fellow users here on these user-to-user forums, you're not talking to iTunes Support nor Apple.
You can view your account's purchase history via your computer's iTunes : if you log into your account on your computer's iTunes via the Store > View Account menu option, you should then see a Purchase History section with a 'see all' link to the right of it. Click on that and you should then see a list of your purchases.
You can't 'cancel' or delete an account, all you can do is remove your personal info from it and stop using it - any content that you bought/downloaded with it will remain tied to the account.
You may also want to check if you have any auto-renewing subscriptions and stop them if you do : http://support.apple.com/kb/HT4098