all my photos are to big
I would use the Paint program that is part of Microsoft Windows and resize them. After opening the picture in Paint you should see in the upper left hand corner something that says resize. Click on that. You then have the option to select percentage or pixels ... select pixels.
You photo needs to be 100 by 100 pixels. At this point you can see that there is a horizontal and a vertical number. If you set the number that is currently the highest number to 100 then the other number should also change as long as the box next to Maintain Aspect Ratio is checked. You should then do a Save AS and rename it so that you don't overwrite the original.
Alternatively make a copy of the original and open the copy and edit the copy and then you can just save that copy.
You can do some cropping also if needed to try and make the picture a square prior to changing the pixels and saving. This would be the best way to do it.
If you are having trouble doing this then PM me and I will find a way to edit your photos for you. I have a degree in Computer Science and also have taken many Graphic Design classes and these are easy for me to fix in a matter of minutes.
Hope this helps.