Yes (I think)....rather than using Insert Picture...just use Insert Attachment. Insert Picture causes the graphic to be in the body of the email message.
You can try it and see if it does the job.
I don't believe that will matter. I believe it is a function of what type of email message was used (i.e. plain text vs. Rich Text or HTML) and also the email client the person receiving the message uses (and how that email client deals with attached pictures)...potentially more the latter than the former.
I believe these days most current email clients will automatically display any common photo extension attachments in the body of the message. Some clients might have the ability to turn that off.
The only way that I know of for sure that will by pass that is to compress/zip the photos so that they don't have a photo file extension. I am pretty sure that sending the message as a plain text message should also do it, but I am not 100% sure...and even then finding where you can make a message "plain text" getting harder with many email clients as HTML/Rich Text is the norm these days. For example, I sent myself a plain text email message with a photo attached and the Apple Mail client STILL showed the photo in the body of the message until I engaged a "Show plain text alternative" mode for that message.