It should be really easy to identify the problem using the debugger.
Which line produces the error?
I assume it's
xmlRecordList = nodeNote.childNodes();
which means that there is not element with the name 'name', so the getNamedElement() functions returns null (no object) and you can't access childNodes() method of an uninstatiated object.
Check your XML structure and write your code accordingly.
www.w3schools.com/.../default.asp
msdn.microsoft.com/.../System.Xml%28v=vs.110%29.aspx
msdn.microsoft.com/.../system.xml.xmldocument%28v=vs.110%29.aspx