Purchased the game tuesday and i've been stuck at the part where you fight ghost for hours now,i can't defeat them nor run past them.I heard you can summon people to help you if so how would one do that?
"Showing off is the fool's idea of glory"-Bruce Lee
If you are in the area I'm assuming you are in I'll give you a couple tips as well answering your question. To damage the ghosts of New Londo Ruins you'll need to be cursed, there are enemies that can curse you but that's a drastic course to take. There are some items that simulate a curse though. As for summoning people you need to be human and in a place where you have not defeated the boss. As long as another player has put down a summon sign and you are within the range of their level you can summon them.
Just as something to add on, I'm only guessing but the fact you don't know about summoning would imply you are still fairly early in the game. If that's true then I wouldn't necessarily recommend going to New Londo Ruins, even with the ability to damage the ghosts you probably wouldn't last long, there are other places far more suited to your level.
You have to be human, not hollow. Find a summon sign and summon. There is an item you should have picked up before the ghosts called a transient curse, use that so you can hurt the ghosts, or just leave that area as there is probably nothing for you there at this point in the game. Maybe later...but not at the beginning, unless you're grabbing the firekeeper soul.