Do i have to use the original w2 form or can i use a printed one

You can use a printed one. It doesn't matter since the IRS receives the same information.

Can I use regular blank paper or does it need to be perforated paper 

The regular blank paper is acceptable for filing your return.

The W-2 copies must be easily separable or already separated.  Perforations meet this requirement, as does cutting them yourself. 

The regulation is designed so that employees don't have to cut the W-2's themselves.  If the forms are printed on different pieces of paper, or they are cut, then this of course meets the requirement to be easily separable, since they're already separated.