Are these 2 games going to be free for ps+ users?

Currenty (in NA) Need for Speed: Most Wanted is not free, and I doubt it will be free for PS+ members at least any time soon. EA doesn't generally do that.
Minecraft on the other hand, I doubt that too as you just stated "let's face it, it's gonna break the selling record [in the] PS Store" so why would they discount it if it'll sell like hotcakes?

Although I would love for both of these games to be free, I highly doubt that we'll see them anytime soon!

Yes for NFS and No for Minecraft.
As you probably know, NFS: MW was free for Europe 5-6 months ago. My point is that there have been Europe games that came out before North America. For example,
Kingdoms of Amalur PAL region (May 29,2013) ---- NA region( October 1)
Also Binary Domain, Sonic All Stars, Sine Mora, Rayman Origins all came out for Europe first.
Here are the region lists with precise dates.
http://en.wikipedia.org/...h_America)
http://en.wikipedia.org/...AL_region)

As for Minecraft, they probably aren't going to need Playstation Plus to make a lot of money. PS+ games generally are hitting a low and by the game company striking a deal with them, they get more money and publicity. Minecraft won't need that because it's been selling very well on other systems, but that doesn't rule out the chance that Sony will try.