DiscT@2 is for the dye side of a DVD disc. Not a CD-R. For CD-R's you need an old Yamaha F1 or other compatible drive. Your 7203A (which i know nothing about) should work with DVD's and Nero 7. In Nero 7 go to Nero Burning Rom, cancel the New Compilation, and click on Extra - top left. Select Burn Label. or select Burn Label icon - top middle right.
Works basically like LightScribe if you have messed around with that but like i said DiscT@2 is for the dye side of a disc.
Best to burn your disc then use DiscT@2 for the remaining space. If you T@2 a disc before you write data to it, it will be ruined for data later, unless you just want to do a whole disc.
I forgot to mention that LabelFlash is for the non-dye side. You will need special discs for that. With DiscT@2 you can write on any DVD's dye side.