How to decrease the size of all the pictures in folder

*Put all the pictures in the folder
*Open any one picture with microsoft picture manager
*Go to view and select thumbnail
*Then go to edit and select all
*Then go to picture and select resize
*Choose the size
*1024x768 is vry good size to view picture on ur monitor
*for web application 800x600 size is good
*choose appropiate size according to ur need
*One thing important to note that peoples often save many pictures on their computer. Most of them are taken from a good megapixel camera. Memory consumed by these images is very large. one image can take 1-5mb of your computer. If u save thousands of pictures then the consumption of memory is very large. As the question of display of pictures on ur computer, high megapixel image and 1024x768 pixel display the same quality image. So it is better to save ur picture in 1024x768 pixels and save the memory of ur computer.
But before reducing the size of picture, copy all the images in cd or dvd for future use bec if u want to take a large print of ur picture then high megapixel picture is very helpful for image quality. So if u want to take a print out of ur image then save it in high megapixel. But for only view in computer save it on low pixel like 1024x768