Help with Moderation

Hi. I'm on a steep learning curve here, but loving it. So:

I need Site Admin to be able to moderate all posts across all blogs (each member blog won't have more than one new post per week, or possibly even per month) - both new posts and edited posts need to be approved before publication. Pages aren't an issue, as Site Admin will create each new member blog and I've set up auto-creation of the one page required. Comments will be disabled for the entire site, so again not an issue for moderation. I just need Site Admin to have the final click on all new posts, and any edits to already published posts.

I've looked at Andrew's Moderation plugin, and it seems to do what I want except that I don't want the "Report Post" and "Report Blog" functions. Can either the functions, or just the links, be removed/disabled? Which file/script outputs the reporting links? Is it hackable and can someone point me in the direction of the relevant bit?

Another approach I considered was controling what the user can do with User Roles, but none of the pre-defined ones do precisely what I need. I need the user to be able to create new posts on their member blog, and edit them, but not publish them. I believe it's possible to set up custom user roles, but have no idea where to start with that.

Unfortunately, I thought I had this all sorted out, but discovered it was only new blogs that were being moderated. I didn't notice as they were all new blogs at that stage in the trial data..duh! I'm now under time pressure, as I need this in place by Tuesday morning.

So, which approach would be best, and can you give me a start? Is there another approach I haven't considered which would be better?
I really appreciate all the help and advice I've had on this forum already.

Janie