I currently have a 13inch Macbook pro and I love it! Ill go through what you're looking for and explain what mac has to offer in those spots.
Word document program - Mac OS X has a great version of Microsoft Office you can buy and I like it a lot, it is very similar to the windows version.
Video Editing Software - iMovie is hands down the best Video editing software that I've tried so far and if I'm not mistaken it comes with every new mac (along with iPhoto which is also amazing!) I use both those apps all the time.
Durability - I've dropped mine a few times but not from high distances (just off the edge of the chair and stuff) and its never broke. Although dont expect any laptop to survive a drop down the stairs or too many drops from waist height.
MMORPG's - From my knowledge WoW is available on mac but I'm not quite sure if its the latest one or anything. I'm not into that stuff.
Mobility - My 13inch Macbook Pro is very mobile. I take it everywhere, and I have a little "incase" slip cover for it and my backpack has a laptop sleeve which makes it easy to bring around. It is fairly light which is good too.
STORAGE - My 13inch Macbook Pro came standard with 320GB which is a lot, and for I think 2 or 3 hundred dollars more you get a faster processor (yay SPEED!) and 500GB instead of 320GB which is a great amount of space!
I love my macbook and it is really good. You dont have to worry about many viruses like windows users have to dread every day, it has an elegant operating system (and they are releasing a new version in July) you get a good 6-7 hours of battery, and it is very stylish and great!
The only downside to a mac is the price. Mine racked in at around $1500 with all the upgrades.
One thing I will say is if you are getting a macbook, wait until after the release of Mac OS X Lion. That way you will be able to buy your mac with the latest operating software and not have to pay $30 for an upgrade 2 weeks after you buy the computer. Apple has confirmed the release of Mac OS X Lion is sometime in July.
Hope this was helpful!