In Brief: Sailor Mars' first attack, while very powerful and used very often appears to only have one, ironic use; firepower. Consisting of a pure fire energy blast, Mars Fire Ignite helped up the team's offensive power in almost any battle Mars was in, especially in the number of episodes which featured Sailor Moon, Mercury and Mars before Sailor Jupiter and Venus joined up.
Similar to Sailor Mercury's attack, Mercury Bubble Blast, Mars Fire Ignite was renamed for the Japanese Live Action Sailor Moon series as, Youma Taisan which translates as "Monster Disperse". It's pretty much the same attack despite the name change (check out the pics) and really should be treated as such, though this is just my opinion and is not official in any capacity.

Cultural: Fire seems to symbolise in almost every culture, purification and rebirth both physically and/or spiritually and can also be seen as a living entity through which wisdom can be gained (think Raye's firereading or Moses' burning bush and the famous writing on the wall in The (Christian) Bible).
Fire can also be seen to represent destruction and chaos or even war and when you think of the who the Roman god of war is (Mars or in the Greek, Aries) fire seems to have even greater meaning for the character of Sailor Mars.

The Attack: For the live action series attack, Sailor Mars seems to summon fire into her hands which collects and forms a huge ball of fire. When the size is sufficient she pulls it back before releasing the built up energy at her victim.