Hi Chris,
I enjoyed reading the script but I must be honest, I don't think it's an idea that will work/appeal. Firstly with regards to the title there's currently a sit com out called 'old guys', so that might need to be changed. Whilst I think there can be comic potential in people who are getting old e.g 'one foot in the grave' 'dad's army' I'm not sure if elderly people in a retirement home would have the same appeal.
I found the script quite negative in it's portrayal and didn't really challenge sterotypes or perceptions of old people, there was a sense of it having been done before. I think the gag about the old lady being a sex maniac would be funnier if it was more subtle, (like rob brydon's closet gay in Gavin and Stacey) Then it's less blatant and I think more funny, as there was far to much reference to it in the first 10 pages, it would become exausting to the audience if that rate of sex gags was kept up.
Just my 2 cents though, I'm not sure if I know what im talking about. You have the vision I don't.
Just one more point. I advise against using younger actors to play old people. It could end up being a bit like a college revue.