I Personally Use IrfanView to resize my images.
Its easy to use and I've found that saving a file at 30% gives a very small but highly acceptable image for upload.
I Highly recommend this free software.
1. Browse your computer and select your image/photo to resize
2. Select the new size for your picture - use a preset or choose a custom size
3. Optionally, add an effect to your image
4. Select output image/picture quality Lower quality means a smaller file
5. Click "Resize" and wait for the processed images to be displayed