I need to Stop The Service Gracefully

ive managed to stop all the threads gracefully

but im having problems gracefully, stopping the service
small example below
the code below is not the actual code but a way to see whats going on
hope it helps

//on start of a service
public partial class Myservice //inherits in designer
{
    MyThreadManager ThreadManager=null;

protected void onStart()
{
            if (ThreadManager==null)  // 1st call on start of service
            {
                    ThreadManager= new MyThreadManager()
                    if (ThreadManager.InitThreads()==true)     // read
config file, create threads 1 to many, check sql connection
                       {
                          ThreadManager.EnableTimers()  // starts kicking
off Jobs
                       }
            }
}
}

/// code in theread Manager

public Class ThreadManager
{
           private ThreadWorkers[] _aThreads   // inherits BackGroundWorker
           private Systems.Timers.Timer[] _aTimers
           private MyLogger  Log;
            public ThreadManager()
            {

            }
           public InitThreads()
            {
                 //.. read config
                  // set up logging
                  this.log = new MyLogger();
                  this.Log.CriticalEventHandelerDelegate+=CriticalEvent
// method of this class
                  //check sql connection
                  //create threads and initilize threads
                  //CreateTimers

            {

            public void RunJobType1()   // called by timer[0]
             {
                        this._aTimer[0].Enable=false;  //below kicks off
all jobs of this jobtype
                         for (int x=0:x<_aThreads.Length;x++}
                              {
                                           if (_aThreads[x].Jobtype=1 &&
_aThreads[x].isBusy==false
                                                   &&
this._StopRunning==False)
                                                {
                                                      int TmpId=
this.GetNewJobId()
                                                      if (TmpId>0)
                                                          {
                                                              this._aThread[x].JobId=TmpId;
                                                               this._aThread[x].RunWorkerAsync();
                                                           }
                                                 {
                               {

              }
             //so a job has been kicked off above and down somwhere a fatal
event occurs i have a Event in the logging Class that if connection error
query error occurs when writing logs
             //fires a CriticalFailure Event..
    public void CriticalEvent(CriticalEventargs e)
    {
         // all the threads come here on critical events
          lock (this)
          {
                if (this._StopRunning==false);    // lets all threads know
not to work
                 {
                     this._StopRunning=True;
                     this.StopWorkers()   // waits for each thread to
finish its job...the jobs dont matter if  thery error or not the worker
always complets , errhandling is done in the business logic
                                                      //thread just runs
the business logic class
                   // once im  back here...i am ready to shut down the
Service....as u see im below the service class  i have a Reference to the
service class  ._Service
                   //when i try to stop the service the executable just
hangs...
                    whats the best way to stop a service from this
point...or do i need to get back up to the service level
                  {
           }
      }
}