Atheists, by definition, believe there is no higher power. So they do have a belief system.
Agnostics choose to believe that mankind does not possess the ability to prove or disprove the presence of a higher power. They believe there may (or may not) be something out there, but until there's proof, they'll just sit on the fence.
Theists believe in a higher power.
I guess, if you don't like being proven wrong and you want the safest row to hoe, then be an agnostic. You don't have to believe in (or disbelieve in) the presence of a higher power. Just say "I don't think we have all the facts to prove or disprove it". It's a very PC approach to deities, and is an oft used belief system by scientists and rational thinkers.
To be a theist or atheist, you have to be pretty sure of yourself and committed that you know a truth. Nothing wrong with that, as long as you don't go around waving a flag selling your belief system (I would say agnostics waving their "belief" system flags are as obnoxious as staunch theists and atheists).
The safest belief system is one you can hold as your own. And when you do find it, do us all a favor and shut the hell up about it. No one cares to hear another person's feckless meanderings on the topic of faith, beliefs, and religions. That is, if we don't count the weak-minded slack-jawed mouth-breathers of society who are easily taken in by the hucksterish behavior of faith peddlers (be it theism, atheism, or agnosticism).
Just be your own person, find your own belief system, and keep it to yourself. You'll find out soon enough if you were right, when you're dead. If you're a theist, and you're right, then you can praise Jesus/Allah/Vishnu/Other for eternity. If you're an atheist and you're right, then you won't know you're right, because you're dead and you won't even know you're dead....you'll just be dead. If you're agnostic and you're right, then you get to find an answer who/what this power is (and if there isn't, you'll never know, because you'll be dead, and therefore, won't be able to know anything, because you're dead).