PHP Blog needed with optional Images, Video & Links to add to existing website

I need to add a blog and backend with secure login to an existing HTML/CSS/PHP site. I'd like to add a empty template page (already designed) to an FTP of your choosing so you can work on it as I am not authorised to give out any login details.

It will need to layout as the sample images attached, depending on what is in each user's blog entry.

Backend, the uploaded image(s) needs to scale in proportion to a fixed width of 400px (the height will vary depending on the image uploaded) and stack on top of each other down the right side of the page. Frontend, each image will also need a small accompanying caption and the images & captions will need a little padding to keep it away from the main article.

The user needs to embed an optional 860px wide youtube or vimeo video and be able to add Related Links.

Backend should contain...

Add New News Item

- Headline
- Choice of date displayed as Day of Week, DD Month YYYY
- Subheader (first paragraph in bold)
- Article
- Upload images & captions (optional)
- Embed a youtube or vimeo video (optional)
- Add related links (optional)

Hope you can help.