Most Linux distros, including Opensuse, have an SFTP/SSH server called OpenSSH installed and active by default. An FTP server and a telnet server are available for download and installation but they are less preferred because they are less secure and have fewer features. You would have to set these up seperately, but there is lots of on-line documentation. I recommend using the SFTP/SSH connection instead.
On your Linux machine, determine the IP address. Start a terminal and enter ifconfig. What is most important is the IPV4 address for the wireless interface, probably something like 192.168.?.?. You will need this numeric address to access your Linux box from the Windows box.
I like to use Filezilla (a free FTP/SFTP client) on the Windows box to access the SFTP server on the Linux box. PuTTY is a popular SSH/Telnet client that can be used to log into your account on the Linux box from the Windows machine. If possible install these software to provide the connection to the Linux SSH server.
For file transfer, use the SFTP client on the Windows computer to connect to the Windows box. I will describe how to do things with Filezilla, but other SFTP clients will do similar things, just sometimes in different ways. Start the Site Manager (File - Site Manager) and create a New Site. For the Host Name, enter the IP address of the Linux Box. Change the protocol to SFTP (if it is not already). Leave the port blank. Set the Login type to Normal. Enter your username and password in the appropriate fields. At this point, you should notice an entry in the left panel which is called NewSite. Click on Rename to allow you to give this entry a more meaningful name. Click on Connect to actually connect with the server on your Linux box. You may have to authenticate the server at this point. Click Remember and accept the connection.
Now that you are connected, you will notice your Windows directory structure on the left panel and a tree-structure of your Linux home directory on the right. Drag and drop the directories and files you want to move. If you want to move lots of files all over the place, you can queue the transfers (Right click on the file or directory - Add to queue) and then once you have selected everything you want to transfer, then tell the program to start the queue (Transfer - Process Queue). Sit back and relax. When done, close the connection (File - Close).
PuTTY or other SSH clients allow you to establish a terminal session to the command-line interface, like telnet does, but in a more secure and feature-rich manner. When you start PuTTY, you will need to establish a connection. Enter the IP address for the Linux box in Server, make sure that SSH is selected and click Connect at the bottom. You then get to log into a Linux session.
If you want to actually see what is happening on your Linux box's GUI, you will need another server, like VNC. I have not configured it, so I don't know how to do things with this.