So here's my way - which gets to be pretty easy after a few goes.
Go to http://imageshack.us/ and create yourself a profile. They will send you an activation link to your nominated email address once you have registered.
Once you have the email, click the link and you will be at the ImageShack main page. Click the Upload Image button on the right hand side. A little popup window appears and you can locate the picture on your hard drive. You can also use this pop up window to resize the picture for the net (takes a bit longer to upload whilst it does the conversion). You can also select to remove the size from the thumbnail. Click OK to upload.
Once the upload is finished, you will see the photo/picture in the 'My Images' section on the centre of the page.
Click the picture so it is highlighted, and again on the right hand side, click the text "Get code for Forums". A window opens with two boxes, the code in the top box works fine for these threads, so click the code, copy it and then paste it into your thread body. This will put a thumbnail picture in the message body and allows people to click it to open and view the full size image.
I like this way because it saves you having to scroll through large photos in one thread.
As for video - I just upload to You Tube and paste the link, pretty self explanatory.
