"I don't know how to shrink an image!"
Your camera takes really BIG pictures, but you don't know how to shrink them, right? Do you just email them as-is to everyone? Did you know that that can create problems for them, like much longer download times or a full email box that doesn't let other's emails come in? Oops! These instructions are for you! :)
When people make mistakes in shrinking images, it may be because they aren't aware that "size" involves three separate concepts:
I recommend 72 dpi.
I recommend no greater than 800x600, typically (and often it is better to have something much smaller, if the details are obvious in the picture).
I recommend a Quality (watch for such a choice while saving the picture in JPG format) about 75-80% of the highest setting. Depending on the software, the Quality value might be called 75% or "8" (out of 10) or "High" (lower than "Maximum").
The most common mistake I have seen is reducing only the Quality when saving the file and leaving the dimensions (width/height) alone (for example, 1024x800 or 2200x 1600). The result is a really "grainy" or "chunky" looking picture.
If you can find how to change these three items in your photo software, you should be on your way to good photo sizes. Don't forget to keep a copy of the original: see "Preserving the original picture."
If you cannot figure out how to change the resolution, dimensions and quality of a picture with your photo software, consider using IrfanView, an excellent, free photo program that can do far more than I describe here.