Oh you're in Newmains; My friends and dad live there, you might see my 126 around there on Sundays once a month!
You can either resize your images to make them smaller in file size or use an external website to host them.
Resize option:Assuming you're on Windows, open the picture in Paint and click resize. In the tool window that appears click Pixels and I'd say resize the image so that the width is no more than 800? You could go more, have a play. Once you click OK it'll shrink the image down, then you just click Save (or Save As) and the file size will have shrunk too. I believe Windows 7 or later actually shows you the file size along the bottom of the Paint window before you even go to save it.
Make sure the new size is no bigger than 80KB
External website option:Go to a free image hosting site, such as
http://postimage.orgUpload your images there, choose the resize option and I'd go for 640x480 or 800x600
Once upload copy the Direct Link
When you come to post the image in the forum, click the
button, then paste the Direct Link in-between the [img] tags that appear