rhizome's correct. It will take more than a weekend with any tech platform to get to the point that you know enough to deploy an app in a week.
That said, with those rather sketchy specs, and no specification of what you already know, Django's on the short list, thanks to its rather nice and integrated admin interface.
For the MVP, if you're serious about the weekend timeframe, I'd suggest considering just sticking with Django's default SQL DB integration and where you see fit, slam some JSON blobs into the database and call it a day. I do mean "considering", it could go either way, but on that timeframe the extra several hours it could take to get something else running starts becoming significant percentages.
If you're willing to loosen up on the time frame a lot of other stuff becomes viable, but in terms of slamming it out now it's going to be difficult to beat Django... tie it, perhaps, but not beat it.
You should probably help us out by telling us what you already know at least a little, in terms of languages at the very least.