MATTER ???

could someone tell me if the senteces are correct and if MATTER could be used like that

1 does it really matter that the anti virus doesn't have a firewall/is it serious if i don't have a firewall
2 does it matter if i have an antivirus or not
3 does it matter whether i come or not
4 what does his name matter/what does it matter what his name is/does it matter what his name is
5 it doesn't matter what my name is
6 what does it matter what people think/what do you care what people think
7 what does his name matter, who care what his name is

thank you