Welcome to the Q&A Forum

Thanks, David!

I own a movie trailer website. (Where you can watch movie trailers)

Will having links on each page that are for "offical website" of each movie, increase my SEO?

I have a site that has around 5,000 pages now.

Are there any recommened online free/paid tools to generate a sitemap for me?

There are quite a few secuirty seals/site safety tools by some big antivirus/trust companies

Mcaffe site secuirty, verisign etc.

Does Google, or any other big search engines use these as a trust/ranking signal?

I have a website that is a desktop wallpaper script.

People can come and upload 100's of wallpapers to share with the community.

This is were the problems comes in.

Files are normally called 27636dark.jpg or whatever and come with no description.

This leads to 2 things.

1. no text content that google can use to know what the page/image is about.

2. Meta descriptions, URL's just look like spam.

Example: /car-wallpapers/7636dark.jpg

If a text description was added, it would still only be like "Green Trees in the distance". Which as you may guess, with 1,000's of wallpapers... would end up having a lot of descriptions the same.

Is there any advice for sites that focus on image driven content?