This is an old old old game, I remember it being spread around by email at work in 2000 (or was it 1999). It's real old style Flash in coding style.

Anyway... Infinite health:
8b 08 00 2f 68 65 61 6c 74 68 00 06 =>
8b 08 00 2f 68 65 61 6c 74 68 00 07

8b 08 00 2f 68 65 61 6c 74 68 00 04 =>
8b 08 00 2f 68 65 61 6c 74 68 00 07

Medals:
Save the Day, 100pts
Beat the game; using the above two cheats it should be easy.

Brutal, 10 points
When you kill the punk in the corridor, shoot him a second time.

Marc Summers, 25 points
Flush the urinals in the boys toilets several times.

Overkill, 25 points
Once you've defeated the telekinetic boss, click on the assault rifle and kill him.

Scat Man, 25 points
Open the door to the trap in the boys and click through whilst having turds thrown at your, after a while you should get the medal.

Tap That, 25 points
Turn the taps on in the boys toilet.

Bruckheimer, 50 points
At the final boss fight, shoot the boiler gas pipe in the top right corner until it explodes.

I only looked at hacking it as I couldn't kill the ninja, my reflexes are just too old :-)