[DI] mac/pc mol modeling ?

[aekentsi at woodlawn.uchicago.edualexemilkentsis]

hi,

i am looking for a mac or pc program to do molecular modeling of small
organics (20 carbons and some heteroatoms). all i need the program to do
is visualize the molecules for me, allow me to do some torsional and
translational motions on them, and be able to print the output.
a plus would be the ability to do energy-minimization calculations.
i need this extremely urgently. can someone point me to such a program?

thanks very much,
alex kentsis.