So you're essentially just making copies of the original CDs. If you are looking to avoid additional software, go ahead and do the .wav file option in WMP.
Just to clarify some terms & concepts here: Any "lossless" codec (like .wav, .flac and others) creates an exact copy of the original music, and (assuming playback on the same equipment) will "sound" just like the original CD. Lossless codecs, by definition, preserve all the audio data and differ only in how they package that data. So none of them are "best" from an audio perspective....the choice of lossless codec should generally be based on what's most compatible with users' playback devices.
And in the context of ripping & burning music files, "secure" simply means error-free. Virtually all high-quality programs (like dBp) have the ability to verify that the copy they just created is error-free.
In your case, where you just want exact copies of your audio CDs, give that .wav option a try. Basically, you'd have a work flow that looks like this:
(1) Use dBp or WMP to rip the original CD to .wav files
(if you've already ripped .flac files, use dBp Music Converter to convert them to .wav files, then proceed to step 2)
(2) Use WMP to burn an audio CD of the .wav files (onto a blank CD-R)
This should create exact audio CD copies of your originals. Of course there are plenty of other ways to do this, using dBp, WMP, and/or other software. A common approach is creating a "disk image" of the original (an .iso file) and then burning this image file to a blank CD. Two good, widely-used programs that can handle both sides of this process are CDBurnerXP and ImgBurn.*
* Be aware that many of these kinds of free utility programs, while perfectly legit and free of malware, are made available through those download venues that like to give you a bunch of their other software by default. Just be sure to watch carefully for options and checkboxes as you download.