That was my favorite RPG this gen (PS3 version). What problems are you having? If it's the controls then you should use a gamepad as from what I hear the PC controls aren't good.
A few (long) tips that will help you enjoy the game more starting out:
1. Stamina is the most important stat (level up endurance to get more of it). You need it to run, roll, swing your weapon, block, everything. This is the #1 most important thing in the game stat/combat wise.
2. Keep in mind the game is unforgiving and expects you to die...a lot. You need to make use of all your different style of attacks for different enemies and only fight 1 vs 1 if possible. You need to think of the combat as if you were really there, block all the time, play defensively, only attack when you create an opening. Lean the enemies "tells" so you can see when they are going to attack and how, and attack/block accordingly. This is not a hack and slash RPG, it's a very methodical game that requires precise attack/defense to do well.
3. Learn the healing spell, to do this you need to get to level 12 faith (you use souls to level up at bonfires), get a tailsman (in the area with the graveyard but not the graveyard just the area, you find one in a chest), you equip the tailsman in one hand and the heal spell in the other (bought by the covenant guy in this same area) and then you can use it.
4. Kindle bonfires that you seem to be using often. To kindle a bonfire you use a humanity (it's an item you get), and it turns you into a human, then you need to use another humanity while in human form at the bonfire (sit at the bonfire and an option will pop up asking if you want to kindle bonfire). This gives you double the healing potions when you die (permanently, it always stays kindled), you can kindle a bonfire quite a few times to get massive potions, but you need to learn to do that later in the game, for now you can kindle it once to get 10 potions instead of 5.
5. The best 2H weapon in the game is the Zweihander and you can pick it up in the graveyard after the tutorial level, just make a suicide run (you will die if you go get it) passed all the skeletons and find it, then just let one of them kill you (you keep your items when you die, you only lose souls). You need to get some titan shards (by killing black knights which don't respawn and are located in specific areas as you go through the game), and level that 2H up to maximum with those shards (which you can't do right away, you need to get to the first blacksmith).
6. You can shoot the dragon's tail early in the game under the bridge for a strong sword that will last you until you can fully utilize the Zweihander. Just Google "Dark Souls Drake Sword how to get" or some variation (YouTube has videos for exactly how), it's very much worth getting.
7. Vitality (health increase stat) is not that important but Endurance is. Endurance increases your stamina which increases how fast you can move, how fast you can roll, how smooth your movement is and how heavy of armor you can wear how often you can block, etc. Dark Souls is about avoiding attacks, not tanking damage. The vast majority of your points is going to go into endurance and your weapon stat of choice (STR for 2H, Dex to 1H). Put a few points in vitality here and there, but certainly not a lot.
8. Always, ALWAYS have a shield equipped. Weapons have stat requirements to use, so get those before you use them. For example the Drake Sword can be wielded 2H without any stat requirement, however to 1H it with a shield you need 16 STR, so don't use it until you have 16 STR so you can 1H it with a shield. For reference the Zweihander requires 24 STR to use properly with 1H.
9. Weapons are good and bad based on their unique attack skills rather than their raw power. For example the Zweihander is the best 2H in the game (IMO) because of it's special downswing attack that stuns almost every enemy in the game for a few seconds, and if you have enough Endurance (as I sad this is the #1 most important stat), you can swing it 3-4 times in a row, stun locking one or even a group of enemies and kill them before they get a chance to hit you. It is that special ability that makes it so good, not its raw power (although when crafted higher using titan shards it becomes very strong). So keep that in mind when deciding a weapon choice.
10. Not all shields are created equal. The most important stat of a shield is the physical damage reduction. You want this number to be very high (at least 95% but 100% is best), which means that when you block the shield blocks 100% of the damage. If it's 95% then it blocks 95% of the damage, so you want this stat to be high. IMO there's only 1 shield in the game worth dropping the 100% damage reduction for and that is the Grass Crest Shield (best shield in the game IMO), which increases your stamina regeneration rate and drops your reduction to 95% instead of 100%, and it's worth that 5% loss IMO.
Those are the tips I can think of off the top of my head. Just remember Dark Souls is a game that does everything but hold your hand. It's designed from the ground up to be difficult and complex without telling you what you need to do (it never tells you how to use magic for example), as such don't let it frustrate you, if you keep dying it means you are doing something wrong and you need to figure out what that is. People can go through it without dying once as they learn the game and understand the techniques/strategies required for the enemies/bosses, it's all about learning and understanding how the game works rather than how you think it should work.
Playing a thief... I think this was my first mistake.
Recognised straight away that stamina was the most important stat.
Found that using a shield was crap. So I use a Katana 2h.. sick damage and this is my prefered play style. Rather than block, I dodge.
After dying a lot I managed to level my toon to a dps build that can handle most encounters...infact I one shot 95% of the mobs.
Also, got some pretty high magic damage, the lighting bolt pretty much one shots everything, if I can fire it off in time, one shot includes the bosses too.
My problem with the game is that it is needlessly complex. It would be nice to know exactly where you are going without wandering off into an area with mobs that **** you.
Some of the areas are very samie, which I hate, because I end up getting lost.
That camp fire system sucks, badly. I don't know if its because I played a thief but I had to grid a shit lot at the beginning of the game to raise my stats.
Speaking of thiefs, WTF is so special about the class I choose... its not like you can sneak about like skyrim or any other MMO... it just feels like your in for a thrashing all the time.
Graphics are way dull. You can totally tell its a console port, no graphics settings at all. It's almost like playing in black and white at times.
Theres not enough story in the game, unless I'm missing something.
Then theres the niggly things... like having to walk a half a mile round the other direction because your character can't climb over a create... or step over a rabbit hole.. or something else completely absurd.