I'm a beginner with computers, Theo, and a slow learner, but I figured out how to post pictures with my Windows XP Home Edition. You just bring up the list of your pictures, then over on the left click on 'Publish this picture/file to the web', then follow the wizard. You will need the pictures ID or address, which is best got by right-clicking on the picture, then left-clicking on 'Properties', then copying the ID or address by address by running the mouse over it while holding the left click down and then doing Ctrl+C. Paste what you copied into where it is required by doing Cntr+V.
When you do your posting into this site, where you want to put the picture, click on the Img* box above, then past in the picture ID or address (no space after [img]) then click on the Img* box above again (no space after the ID or address). Finish the post, click on Submit, and the post, with the picture, should come up in the Topic.
Good luck!