Which metal is the most common of all the metals in the earth's crust? What are some of its properties?

aluminium

1) The most abundant elements in the Earth crust are in this order:
oxygen (46%), silicon (27%), aluminum (8.2%), iron (6.3%).
"Note that numbers are estimates, and they will vary depending on source and method of estimation. Order of magnitude of data can roughly be relied upon."
Source and further information:
http://en.wikipedia.org/wiki/Abundance_of_elements_in_Earth's_crust

oxygen is a nonmetal, chalcogen.
silicon is a metalloid
aluminum and iron are metals


2) "Aluminium ( ˌæljʊˈmɪniəm (help·info), /ˌæljəˈmɪniəm/) or aluminum ( /əˈluːmɪnəm/ (help·info), see spelling below) is a silvery white and ductile member of the boron group of chemical elements. It has the symbol Al; its atomic number is 13. It is not soluble in water under normal circumstances. Aluminium is the most abundant metal in the Earth's crust, and the third most abundant element therein, after oxygen and silicon. It makes up about 8% by weight of the Earth’s solid surface. Aluminium is too reactive chemically to occur in nature as the free metal. Instead, it is found combined in over 270 different minerals. The chief source of aluminium is bauxite ore.

Aluminium is remarkable for its ability to resist corrosion (due to the phenomenon of passivation) and its low density. Structural components made from aluminium and its alloys are vital to the aerospace industry and very important in other areas of transportation and building. Its reactive nature makes it useful as a catalyst or additive in chemical mixtures, including being used in ammonium nitrate explosives to enhance blast power."
Source and further information:
http://en.wikipedia.org/wiki/Aluminum

It,s depends what you mean by metals. Pure as in Goldnuggets, or the raw material from which metal is won. The biggest deposits of raw material are Iron ore and bauxit. From the pure metals should be copper and silver.

aluminium is the most common metal in the earth crust

iron is a good choice!

my guess is iron

Aluminum is the most abundant metal in the earth's crust (8.1%) and the third most abundant element in the crust behind oxygen and silicon.

Aluminium.
Its most useful property is its high strength to weight ratio,corrosion resistant,light weight etc

Sounds like a homework question to me.