Greetings all,
I am not entirely sure I understand the problem but here are my thoughts on how to get (according to my understanding) the desired results.
why not create the list once and assign it to a string, then use regex string replacement for your various values;

my $dd_country_str;
unless(open(FILE, "<countries.txt")){
   die "cannot read file";
}else{
   $dd_country_str .= qq*<select name="countries">\n*;
   while(<FILE>){
      if(/(.*):(.*)/i){ 
         $dd_country_str .= qq*<option value="$1">$2</option>\n*;
      }
   }
   $dd_country_str .= qq*</select>\n*;
   close(FILE);
}
###now call the dd_str you just built;
my $first_dropdown = $dd_country_str;
$first_dropdown =~ s/(value="$country_alias_you_want_selected")/$1 sel
+ected="selected"/g; ###XHTML compliant
print $first_dropdown;
.
.
.
[download]

Is that what you are looking for? It seemed from your original post you were going to be using the same list of countries each time, so I just created the dropdown list in a string and reused that each time.
just a thought.
Also you do not need to specify a name for each option within your select. The name of the select is what will be passed and assigned the value of whatever option is selected.
-injunjoel