starting from scratch almost , need advice

I posted a thread here (lazy old audiophile) last month about how to get music from my computer to my speakers. I think I've learned something since - many helpful responses re DACs, etc. Now I have decided to go back to the beginning, almost, and try to determine what is the best way to go. My cost goals are flexible, though I do want good value. I will probably try to find components used here on audiophile. What is fixed is my new iMac and a pair of Kef 205/2 reference speakers. I also have a nice old Technics SL1400mkII turntable and a paragon E tube preamp from the 70's, and a pretty basic (poor) CD player. (1) I understand that some integrated amps are now available with digital inputs, so I could go from the iMac to the integrated amp. Most of these do not have phono stages. If I go that route, can I use the paragon preamp as a phono stage and how? (2) Or I could get an amplifier and use the paragon, but would still have to get a DAC. (3) Or I could get a good SACD that I could also use as the DAC for signal from the Imac (which ones permit this?), or I could get a multifunction SACD, DVD etc, player (I do have HDTV and cable in the same room). I do not think of myself as an audiophile - but I do find that poorly reproduced music bores me. So without being particularly knowledgeable, or knowledgeable at all, I am kind of spoiled when it comes to decent sound. What would you do?