Does anyone know what all fruits/crops can be stored in natural temparature(say 20 degree centigrade) for a year ?

None that I know of. Pretty much anything that grows in less than a year, will die (and in this case turn into a brown ooze) in less than a year unless you preserve it somehow.

Better to use a root cellar (as the name implies, stores roots like potatoes, carrots, onions, etc) as this is a good mid-range storage. Next comes drying which ranges from fruit leathers to pemmican and jerky and on to smoking.

The question is pretty open - does this help?

Hello, I live in Uganda where we do groundnuts agriculture. Groundnuts are what many in the West sometimes refer to as 'Peanuts', but they may not neccesarily be peanuts. They are planted in soft soils and will mature in 3 months. They can be stored in good conditions [not worse than room tampreture] for more than 2 years and will remain intact for as long as they are not attakced by pests. Today in Uganda, people call them G-nuts. They can be roasted and chewed alongside warm or hot a cup of tea. They can be crashed with a grinder to produce a some kind of tasty butter, they can also be used to make a very delicious stew which many restaurants in Kampala (Uganda's capital), call G-Nut stew and can be used to accompany meals that have Steamed rice, steamed Green Bananas (matooke). Over time, Groundnuts have become a major economic driver for the poor people in some parts of the country.
I have done groundnut farming before and I like G-Nuts. I hope by this description you too will like G-Nuts if you have never seen or eaten them before. Googling or using any other good websearch engine will also give you an insight into the subjects of Groundnuts, I believe.