#!/usr/bin/perl

while (<DATA>){
    chomp;
    @record=split(/\s+/,$_);
    if (defined $records{$record[0]}){ # We've seen it before and need
+ to compare the data
        if($record[1] < $records{$record[0]}->[1]){ # we have a smalle
+r value and so should use this
            $records{$record[0]}->[1] = $record[1];
        }
        if ( ($record[4] < $records{$record[0]}->[4]) ){
            $records{$record[0]}->[3] = $record[3];
            $records{$record[0]}->[4] = $record[4];
            $records{$record[0]}->[6] = $record[6];
        }elsif ( ( $record[4] == $records{$record[0]}->[4]) && ($recor
+d[6] > $records{$record[0]}->[6])  ){
            $records{$record[0]}->[3] = $record[3];
            $records{$record[0]}->[6] = $record[6];
        }
    }
    else{
        @{$records{$record[0]}}=@record;
    }
}

for $key (reverse sort keys %records){
    print join ("\t", @{$records{$key}}),"\n";
}
__DATA__
xhahhxha    60    3    hahaghagah    10    1    101
xhahhxha    60    3    jrthtahtat    8    1    110
xhahhxha    60    3    shdgehsh    8    1    150
hsghtahs    100    19    hahaghagah    10    20    200
hsghtahs    100    19    jrthtahtat    10    20    300
hsghtahs    100    19    shdgehsh    10    20    400

__END__
xhahhxha    60    3    shdgehsh    8    1    150
hsghtahs    100    19    shdgehsh    10    20    400
[download]

Ugly but functional