When using the "Attachments" feature, when posting a reply you're limited as to the maximum file size (i.e. 60KB). To reduce the file size while keeping the dimensions (i.e. 640 x 480) the same you've got to use the compression feature of the JPEG file format. To do this you need to have and use graphics editing software to modify the image file's compression percentage.
Have you instead, tried making use of the image tags (e.g. UBB/BBC/Forum Code or HTML), which allow you to place your pictures any place within your reply that you wish?
UBB/BBC/Forum Code Image Tag Example:
[*img]Your_Image_File_URL_Here[*/img] (asterisks in example must be removed for code to work.)
Your image file 2008 Tour 1 A.jpg (640 x 480, 89,852 bytes)
HTML Code Image Tag Example:
(asterisk in example must be removed for code to work.)
Copy of your image file 2008 Tour 1 A.jpg (640 x 480, 58,136 bytes)