How can I get programs to downlaod to HD and not SSD?

[roaddoc326]

So, I bought and installed an SSD with the intent of only having my OS on it. However whenever I download anything like drivers it downloads to my SSD and program files and program files x86 is in it so everything saves onto the SSD. Whenever I move the files to my HD it either gives me an error and if it doesnt give me an error the next time I download something program files and x86 remake themselves with the new download into my SSD.

Is there anyway to chnage the default destination of all downloads? If so how do you do it?

Thanks.

 

[roaddoc326]

Or should all my programs go onto my SSD? Then what should go onto my HD just games? Also a second note...is 128GB big enough to hold all my programs?