just cross check whether the web.xml is valid according to the dtd. I suspect it might not be valid.
If your sample web application is having only jsp's than you need not include it. Just use anytool to create the web.xml file. Cross check it's well-formedness and valid ness. I think you need not include the context.xml file when you already placed the folder in web-apps. Still any problem just ping me any time on firstname.lastname@example.org