The real issue isn't your laptop. The real issue is lazy inconsiderate posters who won't take less than one minute to resize their photos before they post them.
That right, you know who you are. Half the damned posted graphics won't fit on a 23 inch monitor nevermind a laptop.
Ita annoying and with the plethora of free, easy , and quick to use programs available, there's no reason not to take the few seconds it does take to resize the graphics.
Here's one very good one ... there are plenty to choose from.
http://www.faststone.org/FSResizerDownload.htm
***edit .. on a side note, I can't believe there isn't some kind of "plug in" for the forum software itself that simply resizes graphics on the fly, behind the scenes when they are uploaded.
Not to diminish the old saying ... " if bigger is better, then too big must be just right."