TRegistry enables you to read registry entry.

Below code shows the sample to read registry entry.

uses
  System.Win.Registry;

.
.
.


procedure TMainFrm.LoadConfiguration;
var
  myReg: TRegistry;
begin
  myReg := TRegistry.Create( KEY_READ);
  try
    myReg.RootKey := HKEY_CURRENT_USER; // or HKEY_LOCAL_MACHINE
    if myReg.OpenKey('Software\Junpa Encoder\', true) then
    try
      edTargetDir.Text := myReg.ReadString('TargetDir');
      cbMediaType.ItemIndex := myReg.ReadInteger('MediaType');
      cbVideoResolution.ItemIndex := myReg.ReadInteger('VideoResolution');
      cbVideoCodec.ItemIndex := myReg.ReadInteger('VideoCodec');
      cbAudioCodec.ItemIndex := myReg.ReadInteger('AudioCodec');
      cbSplitMedia.ItemIndex := myReg.ReadInteger('SplitMedia');
      cbDeleteAfterConversion.Checked := myReg.ReadBool('DeleteAfterConversion');
      cbAutoChangeDir.Checked := myReg.ReadBool('AutoChangeDir');
    finally
      myReg.CloseKey;
    end;
  finally
    myReg.Free;
  end;
end;

procedure TMainFrm.SaveConfiguration;
var
  myReg: TRegistry;
begin
  myReg := TRegistry.Create( KEY_SET_VALUE);
  try
    myReg.RootKey := HKEY_CURRENT_USER; // or HKEY_LOCAL_MACHINE
    if myReg.OpenKey('Software\Junpa Encoder\', true) then
    try
      myReg.WriteString('TargetDir', edTargetDir.Text);
      myReg.WriteInteger('MediaType', cbMediaType.ItemIndex);
      myReg.WriteInteger('VideoResolution', cbVideoResolution.ItemIndex);
      myReg.WriteInteger('VideoCodec', cbVideoCodec.ItemIndex);
      myReg.WriteInteger('AudioCodec', cbAudioCodec.ItemIndex);
      myReg.WriteInteger('SplitMedia', cbSplitMedia.ItemIndex);
      myReg.WriteBool('DeleteAfterConversion', cbDeleteAfterConversion.Checked);
      myReg.WriteBool('AutoChangeDir', cbAutoChangeDir.Checked);
    finally
      myReg.CloseKey;
    end;
  finally
    myReg.Free;
  end;
end;