Hi, I don't know if you already have many responses, but I will put in my two cents also.
I was wondering if you used any photo applications?
Having a photo editor makes things a lot easier. Photoshop Elements is powerful, but easy to use. In fact, there are many tutorials on this site about Photoshop Elements. A quick and easy way to get images resized is to batch process your entire file of images using an action. It sounds more complicated than it is, really. It allows you to run an action on your entire folder and resize all your images at the same time. If you do this all the time, you can create a droplet on your desktop and and just drag your folders of new images over it and it will automatically resize for you.
If you just want to upload and not have any editors, Shutterfly is really easy to use. I looked at the Picasa site and it seemed pretty easy also, but I could not find a resize section in my first pass.
With Shutterfly you can resize and email all through their process. It is free, also.
http://www.shutterfly.com/
Hope this helps.
Caroline Thompson