Programming language querry

[Leonard N. Bloksberg]

I'm getting sick of waiting for some specialized applications to be written
for me, so I'm entertaining the idea of writing my own programs.  I am 
comfortable in DOS and UNIX, but I only have access to DOS and Windows 
machines right now.  I'm leaning toward a C language because I understand 
that programs can be compiled for UNIX, DOS, or MAC from the same code.
Is "Borland C++ 4.5 visual" a good language to dive into?  Can anyone recomend
something that will be both easy to pick up, and powerfull enough to bother 
spending time to learn?  Thanks.
.
Lenny Bloksberg
bloksber at pilot.msu.edu
.
.