Change Vbulletin Forum Settings

I am looking for someone with knowledge of vBulletin to do two things for my vBulletin site. 1) Change the attachment settings. Currently .jpg attachments are too small when users click on the image. In fact, when users click on the image, the image is *smaller than* the image in the post. I would like to change this so that the image pops up larger than the image in the post. This will enable users to view these images, as they are important to the forum. 2) Create a private forum for the website. I would like to add a private forum to the existing vBulletin website. The main forum is free, but this forum will be by invitation only. Please only bid on this project if you are good with vBulletin. In the past I have had freelancers attempt to do vBulletin work and they were unable to complete it.... so please only bid if you are very good with this software. Thanks!