I have the oblivion goty edition, with knights of the nine and shivering isles. I tried playing it once before, but stopped when i met some lowly skeletons (this is the spoiler) that were so hard to kill i used up the energy in my two big swords.
What is a good fighter build? How do you fight? Dont remember if u need to block and such or just swhing away. Is bow/sword combo good? I think that would be pretty cool to fire bows at long range and then fight with sword at close range.

You can certainly do the bow/blade thang, many characters have used this successfully.
You can always turn down the difficulty, mid-combat if you need to.
Do you want to use magic as well? Magic can work wonders.
For a first-time fighter/bow guy, I would do:

Blade
Block
Marksman
Restoration
Light Armor
and you fill in the other two....

Born under maybe the Lady, or depending on whether you are using magic, I would use the Mage or the Thief. Follow the Main Quest until just after Kvatch... this should get you some good armor and weapons, and at least a point to start...

the stock knight build has illusion as a major skill. that is the only magic that class has. pure classes are going to have a harder time than a mixed class.

Thanks for the tips. Do i need to patch?

The only reason that you'd want to use light armor is so that your encumbrence is less in the beginning. When you get to the better armor (glass, ebony, etc) the heavy armor has the '0 weight' master perk, and is better to use in combat. Just FYI.

ALCHEMY

Do you mean, use the official patch? That's always a good idea. It helps with a lot of CTDs. I would also suggest loading the unofficial patches,which deal with a host of errors that gamesas never fixed.

The saves wont disapear, if i patch, right?
ZakariusSvedlin, after reading your character creation guide, i choose alchemy as one of my majors, thanks for the tips.
Is it wise to randomly create junk potions, to raise the alchemy skill? Then just selling the potions.. I pick up ingredients as i travel in the landscape.
I didnt choose the bow skill, instead i chose two mage skills, healing and summoning. What are good ways to raise those skills? Do you get increase in the healing skill if you use healing, even if you are not hurt? Thus constantly casting heal when traveling about?

If Alchemy is a Major, I would only use it to create potions when you need them, not when you want them. Otherwise you might level too fast. There are other ways to make money in this game.
For Healing, I use the very weak self-healing spell up until I am about level 50. It's the quantity of times you do something, rather than how powerful a spell is, that counts towards leveling. And as Restoration levels very slowly anyway, this helps out. You gain experience for healing yourself when not hurt, although I don't run my character this way.
For Summoning, just purchase, or you might already have a weak summons. Use this spell all the time. It also is a good distraction for the enemy in combat.

I sell a lot of junk potions. I keep ones that restore health, restore, magicka, cure disease, damage health, and fortify attributes. It will always work if you remember to use it. When you use alchemy like I do, its a major focal point. I mean I buff the hell out of my characters. The uses for it are endless you just have to remember what you have, what you can make, and what you need.

The people who say you level too fast only think about the restoration potions. The Fortifications are where Alchemy shines. It does level you up fast, you will be reliant on it, but it will always be able to handle whatever you run into. ( I know this because I have made a character based on Alchemy with no other real combat skills)

Master alchemy takes almost no time to get once you have access to the Garden at the Mage Academy, and its so strong that its game breaking. Hell Journymen Alchemy is pretty awesome.

Summon monsters and fight them, then heal yourself. Yes I do believe you can increase Restoration without actually healing... its just a very very slow skill.

Any tips on getting started with the summoning skills? I wanto summon monsters who fight with or for me.

Is there a guide to alchemy? How it works?

At low conjuration skill, even a skeleton takes a lot of magicka to summon. Go to Edgar Vautrine in the IC market district, buy the Bound dagger spell, and use it often. Conjuration is one of the fastest skills to increase, so maybe better as a minor skill if you don't want to level too quickly. Make sure to go to Chorrol, the Mages' Guild there have lots of conjuration spells for sale.
As for alchemy :
http://www.uesp.net/wiki/Oblivion:Alchemy
has plenty of information.

Thanks.

My pleasure.
This is useful, pick an alchemy effect, it tells you what ingredients you need :
http://www.uesp.net/oblivion/alchemy/alc_calc.php

Forgott.. How do you use potions that do damage? To hurt enemies?

Select them and apply them to yoru current weapon

Looking at my character i noticed that i hadnt chosen the summoning skill.. Is it still possible to use that magic? Where should i start with a very low skill?

Is raising intelligence the only way to get permament mana increase?

Unless you find or make fortify magicka items, raising int is the only way to get more magicka.
Go to Edgar's discount spells, in the market district, buy Bound Dagger, cast it until you are apprentice in conjuration, then you can use summon skeleton or zombie. If you raise conjuration by 10 points a level, you are guaranteed +5 intelligence on level up.

Just to reinforce that recommendation for Bound Dagger - the reason this particular spell is good for level-raising is that you can sheath the weapon to end the spell before its time expires, and then cast again. All the other bound items make you wait out their timer, so you can't use them so quickly.

And before anyone brings it up, you can cast dispel on self to short-circuit a spell, and level up Mysticism at the same time, but because both Conjuration and Mysticism are Intelligence schools, you're not going to level efficiently that way.

When I intend to use Conjuration a lot with a character, I usually make it one of the majors, just so that the skeleton is available from the start. Those characters tend to have all their other majors selected so they won't be used, and Conjuration is effectively controlling when they level up.