Saving php file in ANSI no isuess but when saving the file in UTF-8 format for various reasons remember to save the file without any BOM ( byte-order mark) support.
Otherwise you will face problem of headers not being properly sent
eg.
<?php header("Set-Cookie: name=user");?>
Would give something like this :-
Warning: Cannot modify header information - headers already sent by (output started at C:\www\info.php:1) in C:\www\info.php on line 1