dependent drop down list (pre-filled from XML file)

Hi,

I have an XML file that looks similar to this:
<XML>
<continents>
<continent name="North America">
<country name="Canada">
<city name="Winnipeg"/>
<city name="Toronto"/>
</country>
<country name="USA">
<city name="New York"/>
<city name="Los Angeles"/>
</country>
</continent>
<continent name="Europe">
<country name="England">
<city name="London"/>
</country>
</continent>
</continents>
</XML>


On a webpage, I would like to do the following:

3 dependent drop down boxes (select controls) and a "go" button:
1 - Continents
2 - Countries
3 - Cities
Button "Go"

When a user selects a particular continent, the available countries and
cities are displayed in the respective drop down box.
When the user selects a particular coutry, only the cities for that
country are listed.
Then, the user can select a city.

The user clicks the "Go" button and then the user is taken to that
webpage.


What I need to know because I don't know XML, is this possible?
how do I store the path with the city in the XML file?
How do I get this whole thing to work for all (at least most browsers)?

Thanks