Well, I started as a pyro, I want to end up being able to fast roll with 'large' weapons. Going to use the man-serpent greatsword after I defeated the boss in Anor Londo. These are my current stats:
http://i.imgur.com/WnDGCGe.jpg
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I have made the mistake of going all out STR I think. Put some in Dex early on, and very few in VIT...
At the moment, using a +10 butchers knife. So kill the boss, then go back to Sens fortress, farm the black knight dude with the item ring for a bunch of large titanites (that will take a while!) and get the MSG to +10.
Those stats are fine if you're going for a proper STR build. Most people stop levelling when they reach SL120 or so, as that's the community standard PvP level, but if you're not worried about PvP, then you can simply keep going (I have one character at SL150+ that I just mess about with now).
If you want to fast roll with a large weapon, you'll want to get your Endurance to 40 as quickly as possiible (not much point levelling beyond that, as you don't get any Stamina boost after that, only Equip Burden), then keep your Equip Burden below 25%. You could use something like Havel's ring or the Ring of Favor and Protection to get an increase on your Equip Burden. Being below 25% Equip Burden to fast roll, especially with a large weapon, will limit your armour choices though, and you'll be pretty restricted to the lighter armours. This isn't always a bad thing though, as being less resistant to hits will train you to dodge and block better.
Ritsugamesh is right as well, if you're after Large Titanite Shards, get yourself to Blighttown and run the bottom floor to farm shards. Head out from the bottom bonfire and you can make a loop of around 23 slugs in 5 minutes (just mentally counted them, I know that run far too well!), and with the Gold Covetous Serpent Ring you'll pull in plenty of Large and Green Titanite Shards.
Have a play about with this site, it's great for looking at how your build could go, and what weaponry and equipment you can use -
https://mugenmonkey.com/darksouls/