Some background to understand all these formats and their relationship:
PCM is Pulse Code Modulation and is a raw audio format - a sequence of numbers that represent the analog signal at points in time. For example, a CD contains 16 bit / 44.1 kHz PCM which means there are 44,100 16 bit numbers for every second of audio (per channel). To 'play' those numbers they are converted to analog via a Digital to Analog Converter (DAC).
PCM is the underlying format for pretty much all of the compressed formats, whether they are lossy (MP3, AAC, WMA, etc) or lossless (FLAC, APE, WMA lossless, etc). When you ripped a CD, EAC or whatever tool you used read the bits off the CD and now has the PCM samples. If you save it as-is, you'd have a WAV file. A WAV file is uncompressed PCM, which is why the file is large.
Now, you can take the raw PCM and convert it to a smaller format to save disk space. LAME is an MP3 encoder so if you have EAC send the data to LAME to be encoded the result is an MP3 file. MP3 is a 'lossy' compression format - it reduces the file size by discarding data that its model believes you wouldn't be able to hear anyway. To play back MP3, the player must recognize it as MP3 and decode it back to PCM for playback. Nearly all media players nowadays recognize MP3 and many CD burning apps will let you add MP3 directly to its burn list because it will decode it to PCM before burning it to a CD.
FLAC is also a compression format but is 'lossless'. Think of it as being like WinZip - it reduces the size of the file but nothing is lost. When it is decoded you get back the original PCM. To play it or burn it to CD, it also must be decoded to PCM. There are very few media players or burning apps that recognize FLAC and can automatically do the converstion for you. So... you have to do it manually by running the FLAC decoder against every FLAC file you want to decode. The docs that came with FLAC should tell you the command line you need to run it to decode FLAC files.
Now as an aside, are you starting to think that using FLAC or any other lossless format that is not widely supported by available tools kind of a waste of time given that disk storage is growing larger each year at a cost of about 2 cents per gigabyte? I do and therefore just save the uncompressed WAVs on a large external drive.
