I\'ve been working with a lot of FORTRAN 77 lately, and though I had reservations at first, I now see some great qualities of the language. It is:
I assume you are considering small, dedicated programs written to solve specific problems. In that case, if the complexity of OO really bothered you I'd just write a C# or Java app and not use OO. Visual Basic should be pretty darn fast these days as well.
Nearly all compiled languages will be mathematically quick these days, all operations are done on the math co-processor--so unless you have found some language to be particularly lacking I wouldn't let any languages "math speed" bother me much.