I am using a Smsung NV 100HD digital camera, in Auto mode I can't turn on the flash The tuch icon on the screen don't turn on.

Follow the instructions on page 32 of this manual.

It's probably because you have enabled the slow sync flash mode.
To switch to the normal flash mode (auto flash) press your left directional key until the flash mode indicator near the top left of the screen (an icon with a "lightning" symbol) changes to an icon with a letter A next to the lightning symbol.
The slow sync flash mode is different from the normal flash mode; in this mode, the camera exposure duration can be a few seconds and the flash actuates at the beginning of the exposure. Although this is useful for certain photography techniques, you have to enable normal flash mode to take pictures in the normal way without blur.

As long as jog dial is set to M or manual, the flash will not pop up automatically. Be reminded though because you have to set everything manually. If you want the auto settings without the flash, set the jog dial to the icon that looks like a lightning with stop/ no sign

First of all, the flash can not be turned off in "Auto" mode. You can turn it off in any mode other than Auto. Would recommend Program "P" mode, which is very similar to Auto, but allows you to modify certain minor items such as flash and white balance.

Rotate your mode dial to "P", then press the button on the back with the "lightning bolt" icon. Press until the lightning bolt with a slash shows up on your LCD screen. The flash is now turned off in Program mode. Try taking a picture.

Remember, if in low light conditions you'll need to keep the camera extra steady without flash to get a clear picture. Recommend placing the camera on a table or chair (or even better, use a tripod), then using its autotimer to snap the picture.

When this camera is in "Auto" mode the only flash functions available are Auto or Flash Off - in order to get the option of "Flash On" for all pictures you have to put the camera in "Manual" mode - to do this:

-Set the mode switch to the camera icon
-Press the "Func./Set" button
-Use the left or right arrow keys to set it to Manual mode (its icon looks like half a camera with the letter M beside it)
-Press the "Func./Set" button again to save your mode change.

Now when you press the flash button and cycle through the choices there will also be a "Flash On" option.

go into setup menu and turn on the smile detection. go to photo and press the right arrow should have a pict of flash icon . press until the flash says auto.

In all of modes you can use "up" key to toggle between "always on", "auto"  and "off" mode for flash. (in some mode there is only auto and off.) also the flash light icon on top right of screen shows th status of flash. I hope this helps...

Low shutter speed icon means that when you take photo the image will be blurry if camera moved.

Is there this icon when flashlight is turned on?

This happened to me too!
Turn the dial to setup, push the menu button & select reset all. This will restore the defaults & let you use the flash again.

Turning the Flash Off and On: 1. With the camera in any user set, repeatedly press the Flash/ISO button on the lens barrel until the flash cancel icon (a lightning bolt in a circle with a slash through it) is displayed on the control panel and screen. 2. When finished, to return to the default setting, press the Flash/ISO button until AUTO and the lightning bolt icon are displayed on the control panel and no flash icon is displayed on the screen. If it still doesnt help: 1. Check that batteries are fresh. 2. Check that camera hasn't been set for no-flash mode. 3. Give the flash time to charge before pressing shutter.