看高手怎么优化这个程序，使运行速度提高

[bgft2008]

Unit_SearchDir.pas 部分

unit Unit_SearchDir;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ComCtrls, FileCtrl;

  procedure FindFile(DirName:string;var FileList:TStrings; IncSubDir:boolean=True);
  procedure delay(msec:integer);

type
  TForm1 = class(TForm)
    Button1: TButton;
    ProgressBar1: TProgressBar;
    ListBox1: TListBox;
    Label1: TLabel;
    procedure Button1Click(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure delay(msec:integer);
var
  FirstTickCount : real;
begin
  FirstTickCount := GetTickCount();
  FirstTickCount := FirstTickCount + msec;
  While FirstTickCount > GetTickCount() do
  Application.HandleMessage;
end;

procedure FindFile(DirName:string;var FileList:TStrings; IncSubDir:boolean=True);
var
  DS:TSearchRec;
  i,p,j:integer;
  Path:string;
  DirList:TStrings;
  F: TFileStream;
  buff: array[0..100] of char;
  NotNul: boolean;
begin
  i := 0;
  DirName := ExcludeTrailingPathDelimiter(DirName);
  DirList := TStringList.Create;
  DirList.Add(DirName);
  while i < DirList.Count do
  begin
    Path := DirList.Strings[i] + '\';
    if FindFirst(Path + '*.*', faAnyFile, Ds) = 0 then
      repeat
        if (Ds.Attr and faDirectory) = 0 then
          begin
            F:=TFileStream.Create(Path+Ds.Name,fmOpenRead);
            F.Position:=0;
            F.Read(buff,100);
            NotNul:=False;
            for j:=0 to 99 do
            begin
                if (buff[j]<>#00) then
                begin
                  NotNul:=True;
                  break;
                end;
            end;
            if not NotNul then FileList.Add(Path + Ds.Name);
            F.Free;
          end
        else
          if IncSubDir and (Ds.Name[1] <> '.')  then DirList.Add(Path + Ds.Name);
      until FindNext(Ds) <> 0;
    Inc(i);
    p := i * 100 div DirList.Count;
    if p > Form1.ProgressBar1.Position then
      Form1.ProgressBar1.Position := p;
    FindClose(Ds);
  end;

  DirList.Free;
end;

procedure TForm1.Button1Click(Sender: TObject);
var
   FileList:TStrings;
   Dir: string;
begin
   if SelectDirectory('请选择检测路径','/',Dir)=true then
   begin
     Listbox1.Items.Clear;
     Button1.Enabled:=False;
     FileList := TStringList.Create;
     ProgressBar1.Position:=0;
     FindFile(Dir, FileList, true);
     if FileList.Count=0 then Listbox1.Items.Add('NO DUMMY FILES!!!')
     else Listbox1.Items.AddStrings(FileList);
     FileList.Free;
     Button1.Enabled:=true;
   end;
end;

end.

[bgft2008]

Unit_SearchDir.dfm 部分

object Form1: TForm1
  Left = 337
  Top = 188
  BorderIcons = [biSystemMenu]
  BorderStyle = bsSingle
  Caption = #26816#27979#20809#30424#22403#22334#25991#20214
  ClientHeight = 239
  ClientWidth = 418
  Color = clBtnFace
  Font.Charset = GB2312_CHARSET
  Font.Color = clWindowText
  Font.Height = -12
  Font.Name = #23435#20307
  Font.Style = []
  OldCreateOrder = False
  PixelsPerInch = 96
  TextHeight = 12
  object Label1: TLabel
    Left = 24
    Top = 208
    Width = 48
    Height = 12
    Caption = #26816#27979#36827#31243
  end
  object Button1: TButton
    Left = 152
    Top = 166
    Width = 107
    Height = 25
    Caption = #26816#27979#22403#22334#25991#20214
    TabOrder = 0
    OnClick = Button1Click
  end
  object ProgressBar1: TProgressBar
    Left = 80
    Top = 205
    Width = 305
    Height = 16
    TabOrder = 1
  end
  object ListBox1: TListBox
    Left = 24
    Top = 16
    Width = 361
    Height = 137
    ItemHeight = 12
    TabOrder = 2
  end
end

[bgft2008]

Project1.dpr 部分

program Project1;

uses
  Forms,
  Unit_SearchDir in 'Unit_SearchDir.pas' {Form1};

{$R *.res}

begin
  Application.Initialize;
  Application.Title := '光盘垃圾文件检测';
  Application.CreateForm(TForm1, Form1);
  Application.Run;
end.

[fangsp]

这段代码写得挺好的啊

[SonicX]

没看出啥问题
procedure delay(msec:integer); 过程没有用到