The only way to obtain a PowerPack is to buy them from Mandrake, or become a MandrakeClub member, I think.
The version of Mandrake that's absolutely free is the Download edition. I'd recommend waiting until the MDK10.0 Official is available to download, as it contains many bugfixes from the 10.0 Community release. It should be available by the end of this month.
The Download edition contains pretty much all you need to get going with Linux, but it does not include proprietory software like FlashPlayer or the Nvidia Drivers. Don't worry, as the free drivers will be enough to get you started and you can install the other stuff yourself. You will get a lot of help from these forums if you run into any difficulties.
To boot from a CD you will indeed need to grab the .iso images and burn each one to a CD. Make sure you have 700MB CDs for the job. As I said, they aren't widely available yet.
If you simply cannot wait, may I recommend buying a copy of Mandrake 10.0 Official from somewhere like fastdiscs.com They took about a week to get the CDs to me, but as I am on Dial-up it saved spending the week downloading the .iso files.
Hope this helps.