do one thing, u go to DOS prompt, and type
debug, and u will get a prompt, here u simply type
d and press Enter, u will get a Memory Dump, note the starting address of the dump. u will get something like 1072:0010, this means the programs r loaded from ((1072*10)+0010)th byte in RAM. locations before this one r used by IVTs, some DOS routines etc....so u cannot change it, if u change it, as i said above u will get "Invalid Page Fault" error....