If you want to trade with snuggly the crow it's a cracked red eye orb for 2 purging stones.
Oswald has a few for sale in the tower behind where the gargoyles were... I assume you've killed them already.
If you're having curse problems then try a light armour set, they have better resistance to things like that... Though not standing in the cloud they create is the best solution lol. You should have the thief set by now, and it's got pretty good resistances for the start of the game.
Distance from the dragon? You don't want to be too far, just out of range from it's slam. That's how you bait it into doing it. Don't lock onto it, it slows movement. Just run when it jumps, it's pretty easy to get out the way of. Just make sure you're not weighed down, ideally you want to keep your weight below quarter of your max for full movement speed + pro rolling. Above half will make you move & roll like a slug.
You can skip the area in the depths with the basilisks if you want. Go behind where the first butcher was, smash the boxes & drop down the hole. Grab the spider shield while you're at it (it's handy for Blight Town). Kill the giant rat if you haven't already, then when you get to the water slide just keep tight against the right wall.
The dragon can be skipped completely though you'll miss out on some easy souls, weapons & one of the armour sets.
If you fancy skipping it, and skipping upper Blight Town (the FPS slowdown on consoles is horrific there) then you can take the back entrance to Blight Town via Valley of Drakes. Make sure you've got lots of blooming purple moss though. The thief set will make things easier here, or if you started as a pyromancer then use that instead. You'll find a pyro set in the swamp once you're down there.
Might be worth popping back to the asylum with the key on the roof in Firelink & grabbing the rusty ring so you can sprint across the swamp. All depends on how you want to play it.