Welcome to the Raven fold! From Monster Hunter to Armored Core... you truly are a sucker for punishment. 
I'm a believer in throwing new players into the fire so that they can come to grips with the most important facets of a game down quickly, so I'd actually advise against Formula Front and will recommend you to Armored Core 3, Silent Line: Armored Core or Armored Core: Last Raven (these three are all separate titles by the way), but then again this is coming from a competitive PvP perspective - the single player tends to stagnate quickly. Also, please note that I haven't played the Formula Front series on the PSP, so I'm not sure if all of this will apply.
Mastering movement should probably be your first priority. Take time to practice boosting in the air and on the ground. Try to expend as little generator energy as possible while keeping mobile. Short taps of the boost button accomplishes this nicely.
Next, try to get acquainted to firing your weapons while moving. This necessitates keeping your lock on the targets while strafing left and right, moving forward, backward, upwards, or downwards. But you're a MH player so I think you're already accustomed to contorting your fingers in weird ways to keep enemies in the camera.
For a nice basic build which is up your playstyle, try making a lightweight machine-gunner.
Like Nix said, feel free to ask about anything. If there's one thing this place needs, it's a revival of general interest in the game, so your questions will be appreciated.
EDIT: Just saw your post before mine. To answer your questions:
1. Correct, energy is used for boosting. Not all weapons will use energy when fired though, only the energy weapons will. However, all parts will require some sort of energy from the generator upon equip (this is what Nix was referring to as energy drain).
2. Heat is a stat put into the game to further control boosting, and to place a penalty on people when they get hit. The heat stat in the boosters dictates the amount of heat that they give off when used. Usually, the more powerful boosters give off more heat, and vice versa. There's a gauge for this, it's usually in the upper left (right?) of your screen. You should see it spike when you get hit, use boosters, etc.
When it fills up, it drains more energy from your generator to go back to normal (I think? Man I'm rusty). In the older games, when you overheated your AP (life) actually took a hit. I'm not sure if it does in Formula Front.
I'm a believer in throwing new players into the fire so that they can come to grips with the most important facets of a game down quickly, so I'd actually advise against Formula Front and will recommend you to Armored Core 3, Silent Line: Armored Core or Armored Core: Last Raven (these three are all separate titles by the way), but then again this is coming from a competitive PvP perspective - the single player tends to stagnate quickly. Also, please note that I haven't played the Formula Front series on the PSP, so I'm not sure if all of this will apply.
Mastering movement should probably be your first priority. Take time to practice boosting in the air and on the ground. Try to expend as little generator energy as possible while keeping mobile. Short taps of the boost button accomplishes this nicely.
Next, try to get acquainted to firing your weapons while moving. This necessitates keeping your lock on the targets while strafing left and right, moving forward, backward, upwards, or downwards. But you're a MH player so I think you're already accustomed to contorting your fingers in weird ways to keep enemies in the camera.
For a nice basic build which is up your playstyle, try making a lightweight machine-gunner.
Like Nix said, feel free to ask about anything. If there's one thing this place needs, it's a revival of general interest in the game, so your questions will be appreciated.
EDIT: Just saw your post before mine. To answer your questions:
1. Correct, energy is used for boosting. Not all weapons will use energy when fired though, only the energy weapons will. However, all parts will require some sort of energy from the generator upon equip (this is what Nix was referring to as energy drain).
2. Heat is a stat put into the game to further control boosting, and to place a penalty on people when they get hit. The heat stat in the boosters dictates the amount of heat that they give off when used. Usually, the more powerful boosters give off more heat, and vice versa. There's a gauge for this, it's usually in the upper left (right?) of your screen. You should see it spike when you get hit, use boosters, etc.
When it fills up, it drains more energy from your generator to go back to normal (I think? Man I'm rusty). In the older games, when you overheated your AP (life) actually took a hit. I'm not sure if it does in Formula Front.
"Let's fight... like gentlemen." - Dudley, SF3
