Congratulations and Welcome to mac-forum! You seems be having a good time with your MBP
By the way, haven't you tried to set up a LAN with the desktop yet? Like you, I have also started windows and by the time I bought my first iMac I had 850GB windows partitions. I didn't know what to do with it until I discovered SMB. Now my PC is my external HD(s). I have also enabled iTunes sharing in my PC so 40+GB of music I have on my PC is automatically listed when I open iTunes on my iMac(no copying was needed).