Wish to parse an entry?

I am trying to check for the content for a xml element but the compiler is not liking the following code

private string GetCriteriaString(XDocument document, ManagementPackView view) {

        List<XElement> queryCriteriaCollection = (from qc in document.Root.Descendants("Criteria")
                                               select qc).ToList();
        string nodeValue;
        foreach (XElement element in queryCriteriaCollection) {
            XmlDocument xmlDocument = new XmlDocument();
            XmlElement root = xmlDocument.CreateElement("Root");
            root.InnerXml = element.ToString();
            XmlNodeList queryParameters = root.GetElementsByTagName("Freeform"); //for freeform-based criteria
            foreach (XmlNode node in queryParameters)                      

                 nodeValue = node.Attributes.GetNamedItem("Value");
                  if (nodeValue.Value == "")
                {

                }else
                {

                }

                 if (nodeValue.Value.StartsWith("$MPElement[") && nodeValue.alue.EndsWith("]$"))
                {
               }                    
                else
                { //might be a GUID. need no conversion


                }

                return  nodeValue.ToString() ;
            }

Its the property I the values which I need to parse?

    - <Criteria>
    - <QueryCriteria xmlns="http://ift.tt/UlhdFK" Adapter="omsdk://Adapters/Criteria">
    - <Criteria>
    - <FreeformCriteria>
    - <Freeform>
    - <Criteria xmlns="http://ift.tt/1c1K19N">
    - <Expression>
    - <In>
      <GenericProperty Path="$Context/Path[Relationship='WorkItem!System.WorkItemAssignedToUser' SeedRole='Source']$">Id</GenericProperty> 
    - <Values>
      <Token>[me]</Token> 
      <Token>[mygroups]</Token> 
      </Values>
      </In>
      </Expression>
      </Criteria>
      </Freeform>
      </FreeformCriteria>
      </Criteria>
      </QueryCriteria>
      </Criteria>