old fashion fermented root beer

hi im just getting ready to make an old fashion root beer using roots, barks, and berries rather than extracts. there was one root beer thread but it was using extracts and a soda keg so i though a new one would be ok. i have a couple questions but first this is the recipe i found:

1 1/2 gallons of molasses
5 gallons of boiling water
3/4 lb of bark roots and berries
1/2 pint of yeast
add enough water to get 16 gallons

question 1: for my first batch i wanted to only make about a gallon to ferment so i don't waste ingredients etc.. the original is made for 16 gallons so this is my recipe:

12 oz molasses
40 oz boiling water
1.5 TBSP bark roots and berries
1 oz of yeast
and then add about 88 oz of water to get 1 gallon

would this work or would it be to chopped up to get the desired results?

question 2: rather then fermenting for 12 hours before being drawn off for bottling could i simply use a wooden barrel and let it ferment the entire desired time for carbonation?

thank you for any help i receive
this is the old fashion root beer recipe source web sitehttp://www.motherearthnews.com/real-food/guide-making-root-beer-zmaz71ndzgoe.aspx

i did more research and found that oak barrel fermentation or aging will produce poor carbonation. but lets say i want 3-5% alcoholic root beer, would i increase the 12 hour fermentation to something like 3 weeks and then bottle to get desired carbonation?

more notes; apparently getting a beer style root beer is slightly more difficult since the time required to get desired alcohol levels the root beer would become a not very sweet liquid. so if i start out instead of soda in mind but beer it should turn out ok. so the root beer ingredients will end up as the hops so i believe ill have to add more; the grain im intending to use i believe will be a burnt rye or maybe the lighter side something like a mixture of rice and barley any thoughts?