Picture size in posts

[Garfly]

How, in this version of the software, do you have pictures display in posts bigger than thumbnail size?

 

 

[red750]

All photos are shown as 300 x 200 thumbnails. Click them to see the larger version.

 

 

[red750]

Further to previous reply, all photos uploaded using 'choose files' below are shown as 300 x 200 thumbnails. Click them to see the larger version. Photos copied and pasted using Ctrl C and Ctrl V appear full size.