Capitalizing the beginning of the expression we use in the middle of a sentence/using quotation mark for expression

Welcome aboard!

I'm afraid your sentence is bursting at the seams! You are trying to put too much into it.

One common way to punctuate a quotation is:

As the saying goes, 'All's well that ends well'.

But a colon, as in your (2) is an alternative.

If you would agree to split the sentence in half we would have:

To conclude, as the saying goes, 'All’s well that ends well'. After analyzing what [has been] elaborated above I firmly believe that the advantages of watching TV are of more significance.

We need 'has been' or 'I have' before 'elaborated'. We don't need the comma after 'above'.

Unfortunately the close proximity of 'conclude' and 'ends well' make it sound as if the quote somehow describes your conclusion. I would suggest,

They say, 'All's well that ends well'. After analyzing what has been elaborated above I firmly believe that the advantages of watching TV outweigh the disadvantages.