A big old bull.....  

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Seems incredible that in 2014 there are people who still can't size a picture for the internet

too big
Pic is too big...
But I recall seeing it too in one of the Recently aquired threads..

Dear tuilp,
If you use Flick...
Dear tuilp,
If you use Flickr, choose medium size when you upload images. It'll then fit the screen.

Its also amazing that this...
Its also amazing that this forum is so terrible when it comes to design and ease of loading photos.

It takes less effort to copy...
It takes less effort to copy the image location and open it in another tab (where it will display correctly) than it does to write a message complaining about the size of the image. I don't get all the complaining and criticism; it is verging on bullying.
I seem to remember reading in another thread that there is going to be an update of the forum software to something more 21st century. That would take care of all the picture resizing issues and a few other niggles. I like vintage furniture, but vintage forum software not so much.

Should not take it to heart
Don't take it to heart, but there is a very clear thread at the top of the forum page about rules and how to upload pics.

Flickr is Impossible
For whatever reason after many, many attempts, I cannot post Flickr pictures either - I even asked the mods to help and they couldn't figure out why mine won't translate either. The Flickr instructions may be outdated or incomplete depending on the type of Flickr account one has. (Flickr has had many changes in the last year)
I finally opened a photobucket account so I can post pictures here without looking like I am unable to follow instructions.
Or maybe lack of posting ability from Flickr has something to do with this (copied from Flickr FAQ) :
Where is the HTML code and photo file link?
The HTML code to embed a photo in a web page that you used to find on the All Sizes page is now only in the Share menu on the photo, to the left of the More menu. We now also include BBCode! (standard message board code)
There are a few cases where the code may not be available: 1) If the photo is restricted. 2) If that person has turned off "Share this" or access to original files.
***The direct link to a photo file is no longer shown on the page. Per the Flickr Community Guidelines "pages on other websites that display content hosted on flickr.com must provide a link from each photo or video back to its page on Flickr." Linking directly to the photo file doesn't do this.***

flickr
Go to "View All Sizes" and copy the image URL for 500 pixel size.
change https to http in image link field.

test
test
Finally success - changing the link properly is not fully described in the DA directions but I fudged it using advice in the Flickr forums. I had to to use the "share" html code/link available on the flickr photo page and delete all of the extra info/characters (as well as the https).