DiabloSport Predator help

[DSMfighter]

I was going to pick up an SCT Excalibrator, but i found a killer deal on a used DiabloSport Predator which has been set back to stock. The previous guy used it on his 2000 Gt, so this should work on my car right? Also with these hand tuners it says that it can:

# Dual timing adjustment points (2000-4000 RPM / 4000-7000 RPM)
# Timing table (+10% / -40%)
# Dual fuel adjustment points (2000-4000 RPM / 4000-7000 RPM)
# Fuel table (+40% / -15%)
# Idle (+/- 20%)
# Raise Speed Limiter
# Rev Limiter
# Cooling Fan ON/OFF Temperatures
# Rear Oxygen sensor disable (use for off-road vehicles only)
# Disable EGR (use for off-road vehicles only)
#It can also Datalog for 90mins. The guy is including the Power Adapter
PC Cable, Manual, and the tuner

I know that not all cars are the same when it comes to the a/f and such, but whats a general good rule of thumb to use when it comes to advancing the timing? Also what benefits is there from diabling the EGR? I know what and EGR does, but not sure of the benefits or removing it.

Sorry for such a long post. I just dont want to get it and not know how to use it. Tuning is my weak pt, but thats why i have u guys. ;D