I Need to downsize 1500 images can it be done in photoshop? But not just one at the time? I Don't know... program photoshop to do the ame to all the images? Something like that?

Try Irfanview. It's an image viewer and batch processing software. I've used it and it saved me tons of time converting multiple images at once.

You can download it for free from their site.
http://www.irfanview.com/

Yes, Photoshop was designed to do that. First you create an action to open the image, change its size, and save it. Then in Photoshop, just do File>Automate>Batch and slect the action that you just created and the folder that all of your images are in. Photoshop will take care of the rest of it.
Regards, Murray

Thank you to both of you