The choice of which language to learn first is largely moot.
All languages share a lot of features: variables, if and while statements, and so on. While the syntax can be quite different from language to language, the major concepts are all the same.
If you learn Java first, you can pick up Python relatively easily. If you learn Python first, you can pick up Java relatively easily.
Perl, while very useful in some situations, is an oddball language. If you learn it first, you might find yourself concentrating on structures that are NOT common to other programming languages. My suggestion is to save Perl for later, and learn either Python or Java first.
Also, if you'd like to be able to put graphical user interfaces on your programs -- rather than just interacting with them through a text console -- Perl may not be the language for you.
- Warren