"You know, if you’re looking for quick fixes and magic and easy solutions, you’re not going to find them," McGuinty told reporters at the Scarborough Boys and Girls Club.
"I think a handgun ban is an important part of a solution that sends the appropriate signal to society as a whole that we are going to draw a line in the sand."
Two people were killed and 24 wounded when gunfire broke out at a barbecue in the east-end neighbourhood Monday night, just one of several nights this week when shots rang out in parts of Toronto.
More than 200 people have been shot in Toronto so far this year, but Monday's deadly shootings outraged the city and triggered politicians into promising action.
McGuinty went to Scarborough Friday to get local input before his gun summit Monday with Toronto Mayor Rob Ford, police chief Bill Blair and Ontario's attorney general and community safety minister.
He said another part of the solution is more police, but there must also be more programs to steer youth away from guns and gangs.
"We understand police are important, but we need to bring a balanced perspective to this," said McGuinty.
"The police are only one part of it there’s another part of it and those are the kinds of programs that reach out to and engage our young people."
Ford doesn't want more money spent on social programs for troubled youth.
"I don’t believe in these programs," said Ford.
"They’re 'hug-a-thug' programs and they haven’t been very productive in the past, and I don’t know why we’d continue with them."
McGuinty called the mayor's comments "unfortunate and short sighted", and said "it reflects a lack of understanding that this is a complicated problem."
Tougher laws and existing social programs have helped lower crime rates, added McGuinty, but clearly more needs to be done.
"So we have been going in the right direction, but the fact of the matter is something is still missing," he said.
"Some tragedies have unfolded of late and this is a complex matter, it’s a tough nut to crack. I think we’ve got to beware simplistic short- sighted solutions."
The premier hopes the federal government will also attend Monday's gun summit at the Ontario legislature.
"I’d be surprised if someone did not come," said McGuinty.
"I think there’s a genuine interest on the part of the prime minister’s office to participate in this."
One of the victims in Monday's deadly incident has been charged with reckless discharge of a firearm, but police have not charged anyone in the two shooting deaths at the barbecue.
Political leaders must take action to ensure Toronto can restore its reputation as a safe city for families, said McGuinty.
"I think that we have a shared responsibility now to do everything that we can to make sure that those lives that were lost were not lost in vain," he said.
"That those families can take some modest consolation at least knowing that we’re going to draw some lessons, painful though they may be, from this tragedy and we commit ourselves to making Toronto safe."