Default Cant find .tar in Odin and dl'd baja but cant wont install

If anyone has any insight on how to get the Odin to find the .tar file that I've downloaded on my pc and can find no problem just not through Odin. Also, Ive downloaded Baja rom but can only find iit in downlaods but it says something used in a program or something or option to overwrite but dosent work, I have latest safestrap. Any info would be great thanks.