Please use code tags for all code, it makes it a lot easier to read. Anyway:

my (@sargs) = @_;
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is it equivalent with : my @sargs = @_; ? (without bracket)

Since @args = already forces list context, yes, they are equivalent. But note that

my $var = @list;
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is not equivalent to

my ($var) = @list;
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my $config = {"delete" => 0, soFiles => []};
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Is it right that $config is a hash table ?

Well, $config is a reference to a hash table; a normal hash is initialized with a list: ( key => value ...) while a reference to an anonymous hash is created with { key => value .. }

is these 2 lines are equivalent ?

my $config = {"delete" => 0, soFiles => };
my $config = {"delete" => 0, "soFiles" => };
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Yes, keys that only contain alphanumeric characters can be left unquoted before the => operator.

You should use an even number of element in a hash, though. (there is NO value for the soFiles key in your example. that isn't possible in a hash)

After that, delete is initialized like this :

$config->{delete} = 1; # why -> is it a reference ?
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why not to use :

$config{delete} = 1
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$config->{ } is used to dereference the reference in $config. the reason that you can't use $config{delete} is because $config{delete} indicates an element in the hash %config, while $config->{delete} indicates an element in the hash pointed to by $config.

You seem to have a reasonable understanding of programming techniques, but a little less sure of Perl itself. You might find the camel book enlightening. Also, putting this at the top of your code will help you spot bugs:

#/usr/bin/perl
use strict;
use warnings;
use diagnostics; # optional; turns on more descriptive warnings
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And we don't usually mind questions, so ask away. :-)