linked lists help please!

Does this look right to you? When I run it, it goes through. No syntax errors. But when I try to declare objects in main on the heap and stack I get an "internal compiler" error. I'm 95% sure that these functions are fine so it must be something in my main. The first function adds a node to the list. The other functin deletes a node. The error says "internal compiler error at [insert some random memory address]"..Generally speaking, what does this error mean? Here is the code:

edit: the error -[C++ Fatal Error] Unit1.cpp(32): F1004 Internal compiler error at 0xc9e04b2 with base 0xc9d0000; I'm using borland

Thank you in advance for any assistance :)

//specification file

#include "theatre.h"
#include 
#include

void TheatreList::insertNode()
{
      string patronName;
  int seatNum;
 cout<<"enter name:"<<endl;
 getline(cin,patronName);
 cout<<"enter seat number:"<<endl;
 cin>>seatNum;

  SeatNode * stalker=NULL, *walker=firstPtr;

  while(walker!=NULL)
  {

    if(walker->patronName >= patronName)
      break;
      stalker = walker;
      walker = walker->link;
  }


  if(walker!=NULL && walker->patronName==patronName)
    cout<<"patron already exists"<<endl;

    else
    {
      SeatNode * builder= new SeatNode;
      assert(builder!=0);
      builder->patronName = patronName;
      builder->seatNum = seatNum;
      builder->link = walker;

      if(walker==firstPtr)
        firstPtr=builder;
      else
        stalker->link=builder;

        cout<<"reserved"<<endl;
    }




}





void TheatreList::deleteNode(int seatNum)
{
  SeatNode * walker = firstPtr;
  SeatNode * stalker = NULL;

  while(walker!=NULL)
  {
      if(walker->seatNum == seatNum)
        break;

        stalker=walker;
        walker=walker->link;
  }

  if(walker==NULL)
    cout<<"seat not found";
    else
      {

         if(firstPtr==walker)
         firstPtr=walker->link;

         else
            stalker->link=walker->link;
            delete walker;
            cout<<"deleted";
       }



//main

#include "theatre.cpp"
#include 

using namespace std;

int main()
{

    TheatreList patron(44,"cats");
    patron.displayAll();
    patron.insertNode();
    patron.insertNode(); //I think this is what is causing the error...hmm



}