PC on some weopons and a question or two

I have a few weopons that I need to figure out what to do with. Any help would be appreciated.

Near MAX.
Purple Vampiric Giant Slayers Hammer
18-35 Damage
REQ 13 Hammer Mastery
Life Steal 2
Health Regeneration -1

MAX
Blue Vampiric Wingblade Sword of Self Defense
15-22 Damage
Requirements 9 Swordmanship!
Damage +11% (Health below 50%)
Life Steal 1
Health Regeneration -1
Armor +4

MAX
Purple Cruel Summit Axe
6-28 Damage
Requirements 10 Axe Mastery
Damage +11% while in stance
Lengthens Deep Wounds Duration

Scrolls:
Hunters Insight - 175% Exp from combat ends if party fails to kill boss in 5 minutes.
Adventurers Insight - For 10 minutes your party gains +50% Exp.

Also, can I change the modifiers on the those weopons by changing the hilt or grip, etc? Will doing that ruin the other bonuses on purple/gold items? I am assuming I can change the hilt or whatever and replace the vampiric for something else without messing it up.

TIA