It sounds like someone needs to research things a little on their own too.
LIPOs when used properly will give you great service, but handled improperly can be dangerous
The 2400 Lipo is a very good little battery, but in a heavy slash I'd probably suggest a bigger capacity battery (lipo or not)
a 2 cell LIPO battery should never be run below 6.0 volts (you can run them down generally to 5.4 volts w/o any real damage, but beyond that can have irreversable damage.)
NiMh batteries can be dangerous too, especially depending on the age of the child playing with them and how they treat them. CHILDREN should never be charging any of these R/C batteries unsupervised.
I've seen hobbyshops sell people Gas powered cars that have NO Clue, and have no idea that FUEL can burn and/or can be dangerous... KNOW What your buying, and read ALL of the precautions.
I'm going to assume for a second that because you said it was a 2400 LIPO that it's probably an ORION 2400
On the outside of the BOX a 2400 LIPO comes in (although it's small writing) there is a LARGE List of Precautions with about 10 things that say
DO NOT and then it lists the things NOT TO DO w/ a LIPO.
On the INSIDE of the box there should have been a BRITE ORANGE paper with the heading
W A R N I N G
USER MUST READ THE FOLLOWING INSTRUCTIONS BEFORE USE!
These precautions shoud be read and taken seriously to prevent serious injury, or damage to personal property from misuse.