Spider fighting tips:
1) Take advantage of your location. Considering a Spider's jump, Having a height advantages is always the best. Fighting from a cliff or under them, will not only stun/ push them back, but allow you to hit them again and blitz.
2) Bring the fight to the water. Spiders only advantage is thier pounce. This is GONE in water. you can just blitz them at this point.
3) Strafe backwards, and try to get a hit in if all else fails. When you connect a hit, blitz back!
Blitz - To hit, and taking advantage of the bounce back from you hitting the enemy. Much like a zombie, blitz-ing can prevent a counter attack and push the mob back repeatedly.
Pretty technical eh?