Try saving your image as a Jpeg or a gif. Depending on what you have installed, MS paint will give you these options. You might currently have the avatar as a bitmap, which is good quality but the file size is huge! If you go to aspect ratio in Paint, you could also just reduce the number to something below 100% and check the image info for pixel size as well.
Burj Dubai (Khalifa) final height = 828 meters / 2,715'... wow!
Current Link status: 81.0!% complete.
A New Costume begins!: 1% complete. Hylian Lore
Arrows Projected: 2,360!
Current FFXIV Status: GLA13