There are a number of file sharing resources. However, the easiest is actually Samba. Out side of using Samba you may have to install something special on Windows to access the shares.
Some common share resources are, NFS and FTP.
Sharing with Samba (easiest)
Microsoft file sharing is already activated by default on Windows machines. It's easily configured on Ubuntu. You might consider posting (in another question) a description of the error's problems you're having with Samba and have a simpler solution.
On Ubuntu you can actually activate the Windows file sharing just by browsing to the folder you want to share (from the default file browser, Nautilus), right clicking on it, then click Local Network Share
and then answer the gui prompt for configuring access. Local Network Share
is also one of the tabs when clicking on properties of a folder.
FTP Sharing
To sharing via FTP install vsftp.
To consider ftp for both uploading and downloading you'll have to edit the /etc/vsftpd.conf
file.
You would have to uncomment the write_enable=YES
option if you want others to be able to upload files to the shared space.
You can manage users by creating accounts for the users you want to give access and uncommenting the local_enable=YES
option.
There are other details for setting it up of which you can get by reviewing ubuntu's documentation page, https://help.ubuntu.com/community/vsftpd.
NFS sharing
Review the Ubuntu NFS documentation at: https://help.ubuntu.com/community/SettingUpNFSHowTo.
For this you would create directories that you want to share and specify the access parameters. For instance (from the documents page):
/export 192.168.1.0/24(rw,fsid=0,insecure,no_subtree_check,async)
/export/users 192.168.1.0/24(rw,nohide,insecure,no_subtree_check,async)
The directories that you specify for sharing are referred to as exports.
Windows will have to be specifically configured to access the NFS shares. You might have to get details from one of the Windows forms for the details of setting up the Windows Client. Micorsoft has provided this page: https://technet.microsoft.com/en-us/library/cc732891.aspx