you can go to a site called photobucket.com ans sighn up for a free account, from there you can upload all of the photos on your computer one at a time onto photobucket and resize them as need be. (all for free) they then host your images, then to use them on a forum sugh as this you copy the adress from from the IMG box and paste it here, and tada the photo will show up without trying to uload it through the forum...
hope this helps!