At least you are making some progress. The 3M setting on your camera probably stands for 3 megapixels which is way bigger than you need and will slow your upload a lot, if it goes through at all. If you have a 1 megapixel setting, use that. Even smaller would be better if you can. Auctiva's maximum size of 1024x768 pixels when multiplied out equals 786,432 pixels, or about 0.8 megapixels, so Auctiva would still have to downsize your pic even at 1 megapixel.
The ideal way is to use a simple photo editing program to control image size, file size, cropping, contrast, and all those other goodies before you upload. That way you are uploading the best image you can create, which will definitely pay off in more bids, higher prices, etc, not to mentions fewer upload hassles. If you do use a editor, then it is best to take the pics at your HIGHEST megapixel setting, and wait until you are through manipulating them in your PC before downsizing them for final upload. That will result in better images.