Manage Colors correctly. And yes you can open CR2 at different sizes through ACR into Photoshop. CS2 files can not be written by Photoshop. CR2 files contain RAW camera sensor data a mosaic image. These mosaics images need to be converted into a color image before Photoshop can work on them. Photoshop does not work with RAW camera data mosaic images..
From Bridge you can select to open your image into Camera Raw, using a right click. You can adjust the color of the image in Camera Raw if you need to, and then select 'open image'. Once in Photoshop you can select 'Save for the web' and that should allow you to save as a jpeg that you can send via email and without any color loss.
Jpeg by its nature is a lossy format, but you should not notice the difference unless you save at low quality. Save at 9 or 10 and it should be fine.
Just want to emphasize that there is no such thing as "not losing quality" when saving a JPEG or otherwise dealing with JPEGs.
What Curt Y says about not noticing the difference is relative and it depends on your personal standards. Most JPEG users will really not notice the difference in casually observing the JPEG. I do, so I avoid JPEGs until someone demands one for whatever reason.