Changing the country setting won't help. You can see the other items, yes, but you can't buy any unless you open an account in the US iTunes Store. This has been covered here literally dozens of times, but once again: the content owners do not allow cross-border sales from any of the legal download stores. You must have legal residence in the country of the iTunes Store you wish to use. So in order to buy from another country's iTunes Store, you must (as proof of residence) have either:
a) a credit card issued by a bank in that country with a billing address also in that country, or
b) a mailing address for your residence in that country
and a gift certificate or a prepaid card that was bought in that country.
If you cannot fulfill one of these two sets of conditions, you will not be able to purchase from any given country's iTMS.
This, again, is due to restrictions placed on Apple by the record companies and other rights holders (who are often completely different from country to country and so all require their own individual negotiations and contracts), not by Apple's choice.