: what programing langauge would u recommend then ???

C is good for anything that needs to be as fast as possible. I have enough faith left in VB to think that it can handle a simple 9600bps serial connection, but who knows.. If you can't get it running properly, then you could try to use WinAPI directly and in C/C++, if necessary.

http://www.dotnetmonster.com/Uwe/Forum.aspx/dotnet-vb/47290/ir-on-serial-port-vb-net-2005
http://social.msdn.microsoft.com/forums/en-US/vcgeneral/thread/4fc63fd0-bf6a-4882-b602-59557a05621c/