I google it and found that Strawberry comes with additional dev tools to compile CPAN modules if necessary. Whereas ActivePerl has a lot of prepackaged modules which are easier to install with PPM. In addition, DWIM Perl contains the standard Perl and a lot of extension and Citrus Perl is a binary distribution of Perl created for GUI application developers. 

Now, I wonder what should I pick to get started? 

Note: I am going to use BioPerl in near future.

http://dwimperl.com/

http://www.activestate.com/activeperl

http://www.citrusperl.com/

http://strawberryperl.com/