Well... your messing about could have done anything.
You are correct that you need to use samba. In general, you select a directory ("folder" in MS speak) to make available to the windows network... usually ~/Public. OpenSUSE has GUI tools to do this. You want to be sure that your selected folder is shared with no authentication to everyone.
Windows networking is notorious for now-you-see-me-now-you-don't problems, especially for home networks which usually include at least one computer with a restricted license (not allowed to connect to more that 2 other machines or some such thing which is totally alien to the FOSS world).
Sometimes, competing for master damain controller status can mess things up. If you have one machine on most of the time, and the others come and go, then you can set the more permanent machine as the master all the time and set the others to never be a master.
What you need is an OpenSUSE samba tutorial...
http://en.opensuse.org/SDB:Samba_fil...ugh_the_window
Of course - all Windows problems go away if you install gnu/linux to all your computers...