Probably the beach. It's common knowledge that zombies can't swim. If Michael Phelps became a zombie or something, then I'd probably just kill him first, then swim out to the middle of the ocean.

What's the best terrian for a zombie attack in my opinion?, Well the best terrain for a Zombie attack in my open would be the open streets in a big city because there are plenty of places to hide above and below ground  and you could also hide out in a huge building.

TheFadedWarrior :
http://www.youtube.com/watch?v=1JXtbbPeL8U

I'd Pick water too but for different reasons.
I dig hunting and fishing but I like real food. So, the docks might be the best spot.
Not too far from real food that is not contaminated.
But the idea of the Zombie is kind of weak anyway.
They can not move fast or replicate. (Other than feeding.)
So, I do not see the Zombie thing as a problem for anyone outside a city. It just makes lunch out of the Rich and/or Ill-practiced person. ( "Ill-practiced"= Not schooled in the arts of staying alive without civilization.)

Good Luck.
Peace.

What's the best terrian for a zombie attack in my opinion?, Well the best terrain for a Zombie attack in my open would be the open streets in a big city because there are plenty of places to hide above and below ground  and you could also hide out in a huge building.

Probably a long, open street with an elevated position, maybe next to a river bank to swim away in.

   To be honest, this is an extremely tough question. I would have to believe it would be the simplest to fend off zombies located at a greatly-sized plain, considering there are enough areas of vacancy to dash around. It would be extremely difficult for the zombies to attack you with all of the space you are provided with.

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   This is an extremely intriguing Thread. I believe I shall include this within my list of Favorites!

For best terrain, I would choose city. There's more people, true, but also more places to hide and more resources (food, water, weapons, armor). I would have to get over my fear of the large population of zombies. For supplies, the safest way I see is to tie a rope from the top of a building (after making sure zombies would have a hard time getting up there by blockading the door), and scale the building from the outside. If I see a room that's not infested and looks like it may have something useful I'll break in using a bat or gun, take what I need and scale back up to the top.  

If I could be anywhere, I would like to be in a military base. The problem with the CDC in WD was that it had all sorts of biohazards that needed to be destroyed once the station lost power. The military base would be impenetrable to the zombies and would have enough food and water to supply an army. 

An abandoned shopping mall is the best place to have an apocalypse. 
Since it is abandoned you can just steal anything for weapons or resources. Don't set off the alarm though until you are ready, all of Zombies will go nuts!!