The people who are not having problems are not getting what the issue is here. I have the same problem on my Eris.
The email that has a "show pictures" or "download pictures" options: either the mail was sent as attachments or the pictures are hosted on a server and Gmail gives you these options.
What is being talked about here are embedded images, i.e. those images that are directly inserted in an html message. Messages from Outlook have this capability as well as certain other programs such as Photoshop Elements.
This may be a bug or a security feature. Spammers use embedded images to report back to a server that the address is good. However, if this was the case, why does the full version of Gmail on the PC allow embedded images to be show.
Also the BB email client displays embedded images properly.