A Spartan could come out of cryo after hundreds of years and have no ill effects or any permanent damage, this is due to their Augmented bodies being designed with this partly in mind. A human however, it would depend completely on that humans physiology and adaptation to cryo, realistically a year in cryo is no different than a hundred years due to your body being in a state of hibernation, preservation,. You would likely have the same ill effects from both time frames, and generally a cryo pod is operated by a source of nuclear and above power, especially on the UNSC spaceships. Halo has went into information on cryo pods slowly over time, and I believe the Forward Unto Dawn series takes alot of steps in that direction, to explain that not everyone has the same experience coming out of cryo as someone else may.
In other stories surrounding cryo people have come out of stasis with somewhat of a jet lag, confusion, sometimes the surroundings they entered from are completely different from those they exit from, this leads to a questioning of ones sanity in most instances, nausea and shock. One of my favorite Animes began similiarly, some of you may be familiar with the anime Blue Gender, if so you understand the elements. The main character of the series developes a uncurable at the time disease, and is selected as a candidate to be put into cryo until a time when a cure has been discovered. However he is awakened many years later to discover he is now inside a facility overgrown by vegetation like a dense jungle, he immediately suffers ill effects, and is forced to snap to soon after as the villians of the series show themselves, a vicious variety of insectoid, parasitic aliens. You can imagine his mental stability reaches a point where he questions himself greatly, and it would perhaps be the same in the event of something similiar taking place in the Halo universe, such as the Spartan you are creating being put into Cryo for hundreds of years and awakening to something even more frightening than his previous encounters.
I dont think cryo statis units have malfunctioned very often in the Halo universe, and normally deaths arent experienced coming out of it in a normal situation. I could however see a bit of bad luck interfering with that normal experience and causing a scenario like you have mentioned Oompa, their survival however would depend completely on what effects they suffer from the forced ejection.