A bit of help for you about picture sizes.
A digital picture is made up of thousands of small squares called pixels.
When you take a digital picture it will be so many pixels wide and so many pixels high, say 640x480.
The better quality the picture the more pixels it will have, so a good quality picture may have 2048x1536.
Now your PC screen is also made up of pixels, so it may be 800x600 or 1024x768 for example.
Now the problem is that if your screen is at 800x600 but the picture you want to view is 2048x1536 it will be too big for the screen.
The web may try to show it at "full size" but some programs may scale it so it fits.
What you need to do is get some photo editing a software (Photoshop Elements is good), open the digital picture, find the mage size, and then change it to something more manageable, 800x600 or 640x480 for example.
SAVE IT WITH A NEW NAME (so you dont overwrite the original picture).
Also keep the same aspect ratio (shape) so it doen't look strange or distorted.
Most pictures are saved a JPEG so keep it as that.
You will find the size of the picture has reduced, but also the size (phyical size on disk) has also shrunk.