I learned to program using Borland Pascal and Borland C in the DOS world. I have to say, to this day, I think Borland's IDE is one of the best ever made. The edit-compile-run cycle is extremely fast, the online documentation (of the language) is superb and easy to use, and associated tools (Turbo Debugger) are great too. If I had to learn programming all over again, I'd choose Borland again. It's a pity the company seems to have lost its way.
For learning C, there should be no disadvantage to using the Borland product. You'll have to relearn some system calls when you move over to a POSIX system, but there's a benefit in learning multiple systems and the differences aren't that great anyway.
For C++, you will run into some more severe problems with Borland C++, but not immediately. I doubt that Borland C++ has decent support for the Standard Template Library (STL). If you're just learning the basics of classes, objects, inheritance, etc, this will not be a problem. After you master these skills, install g++ and go from there...