If you’re familiar with web programming you should be able to be productive with Rails in the time it takes you to read http://guides.rubyonrails.org/
My previous workplace was a .net shop and they decided to build a new Rails application from scratch with a team of four, I was the only one who had experience with it and that was only a couple of toy applications and a few months playing. The three others picked it up almost instantly, knew which questions to ask and found answers in a timely manner. The Rails community seems to agree a lot about the right way to do most things so you’re pretty safe running with the popular solutions.
If you know how you want to solve something programatically then it’s really easy to find a solution in Rails with Google or those guides.
I reckon 1-2 months is about right to learn the Rails way of doing things and be productive.
I’d allow a dedicated 6months to learn the rest (HTML, CSS, Javascript, SQL, OO).
You won’t be amazing, even with 6-8 months of programming experience but you will be able to get things done.
It takes many years to become a good programmer and spot things that cause problems. Rails helps you in this regard by making a lot of good decisions on your behalf upfront.
My intention for learning is that I am tired of hiring developers and waiting for them to finish the product. I like to have social networks created, so the essential features of those websites are stuff I am looking to build (profile, inbox, activity feed, photo albums, newsletter, photo rating, etc).
You might be making a really wrong assumption here that programming is easy.
I don’t know your developers - but I will say the obvious, that developing a product takes time.
Not trying to be a wet blanket, but if you don’t have a passion for it you will probably give up.
I know I will definitely be posting a lot on Ruby forums seeking for help. Hopefully I can come across a mentor to help speed up the process.
Post away, we’re here to help 