I do some light hacking in iDOS for fun as well. Might as well go straight to Borland C++ 3.1 [0] (the "professional" version) over Turbo C++ these days.
When you eventually hit the Great Wall of 16-bit real mode, I recommend switching to OpenWatcom [1], aka "the compiler that built Doom," which comes with something closer (relatively speaking) to a modern toolchain. DJGPP [2] has been recommended as well, although I found it more trouble to set up.