Hard Drives and such

Okay so I managed to get my old hard drive out of my old macbook pro silver beezle 2008 version, but heres the question..
Can I take a previous hard drive that I've had and just install it into my newer 2009 13.5 inch because I have absolutely none of the information that was on my old one, I would love some type of advice. I literally had to pry it apart to get it out. I have over 320 gigs of Hard Drive space on the old one and sadly on the newer model I only have 160 so basically instead of having to spend the money and enclose the old hard drive and do the file migration can I just put it in the optical or is this blasphemous. Just wondering!
Thanks guys!
Kyle.

You didn't tell us which version of OS X the old hard drive has on it, and the version of OS X that the newer machine is now running...?

Personally, I wouldn't put the older hard drive in the newer machine. If you need more hard drive space, buy a larger hard drive and install it in the 2009 MB. As far as using a data doubler to install the second hard drive in your machine, that's up to you. But again, I wouldn't do it as it may not be worth spending the extra money on a 2009 MB.

The old one was @ 10.7.8 and the new one is @ 10.8.3 so the version I don't think should be a problem.

A USB2 case for that drive should be trivially cheap, I would go that route. Even if you decided to swap drives, where then would you put the current newer drive? You can't replace the optical module without spending some (substantive) money ...