I have a card deluxe and I've been copying vinyl with very good results (though certainly not as good as the original vinyl.) In answer to your first question, as you suspect, you will go from your line level out to the analog in on the card deluxe. I assume you have some software to run the thing. You copy directly onto your hard disc, usually into a .wav file. Then, using cdr burning software, you copy onto a cdr in redbook format. You can get decent computer burners for under $200 and they almost always come bundled with the necessary software.
If I understand your second question, while I believe you can copy the digital stream from your Theta to a wav file on your hard drive, you cannot go directly to the cdr for a variety of reasons. But once you have the wav file on the hard disc, you can then copy to the cdr. Of course, if your goal is to duplicate a music cd, why not just put the source in your cd-rom drive and copy directly to the burner using the bundled software?
I know this can be controversial around here, but bits is bits and it won't matter what your transport or cabling is when copying digital to digital.
good luck!
If I understand your second question, while I believe you can copy the digital stream from your Theta to a wav file on your hard drive, you cannot go directly to the cdr for a variety of reasons. But once you have the wav file on the hard disc, you can then copy to the cdr. Of course, if your goal is to duplicate a music cd, why not just put the source in your cd-rom drive and copy directly to the burner using the bundled software?
I know this can be controversial around here, but bits is bits and it won't matter what your transport or cabling is when copying digital to digital.
good luck!