Putty is an SSH client that you log in to your dreamhost shell account with. It’s not clear where you want your file and where it is now. If you need it uploaded to the server, then I suggest you use ftp or some ftp program that can handle interruptions (bullet ftp, flash fxp, etc.).
Once it’s where you want it - I assume on the server - you should be able to log in again with putty and navigate using cd (change directory), pwd (print working directory), to get where you want to be. As for restoring I am not sure I can help you.
Hope that helps.
Not sure which plan is best? This chart lists the plans.