If one of your stack members has only 16 mb flash then the "highest" IOS version you can use (for the entire stack) is 12.2(55)SE9.
You will need to "unpack" the IOS to all the members of the stack. Let's say you have three 3750 in a stack.
The correct command to "unpack" the IOS TAR file to the three members of the stack is:
archive download-sw /destination 1 /destination 2 /destination 3 tftp://[TFTP IP address]/filename.tar