my 2002 mercedes benz s500 gas pedal isnt responding and battery is fully charged but car wont start. sometimes and keeps dying

My 2002 mercedes benz s500 keeps dying
randomly, stating the battery is dead. But i
put 2 differerent batteroes in that were noth
charged and once i get it to start(by jumping
the battery with another vehicle) the gas
pedal isnt respoding, either a delayed
response or just doesnt rrspond at all..
Causing me to cruise at the speed of
ansolutely no gas exceleration at all. Also
my car started over heating during all of this.  
Ive never had any problems with my car at
all what so ever up until these few things.
When i jumped my car the jumper cables
sparked a little bit ao i wasnt sure if i could
of blown a fuse.. And if so its all in italian so
i dont even know where to start .