Why don´t you try out Mihov Image Resizer 0.7 for resizing those images and even jpg-encoding the files?

It might prove to be a solution for you, as 1280x1024 are certainly quite big on the average monitor size many of us run with.

My comment has to do with the fact that all of the replies came with a 5 minutes difference, almost a battle for the first answer, lol.