Okay, I checked the links and the first two look very helpful-you have both readings and the basic translations!
However I can't give you my opinion about the Textfugu book - it looks rather suspicious. I mean there is so much free information on the internet, then why would you give your money on something which might not be helpful enough?

If learning the radicals first is the easiest way for you to learn, then go ahead. But don't forget that the strike order is also important.

Write in Google this: "JLPT Level N5 Study Page" - there you will find all the info you need. JLPT is and abbreviature for Japanese Language Proficiency Test