I used SQL2008 R2 in my local machine, and I was not able to restore the database back to my website on Winhost.
That's not going to be possible. If you want to use our Restore/Backup feature, we can only restore databases taken from a SQL 2008 R1 server. Else you will get an error. Try using the Database Publishing Wizard. See if that will help. http://support.Winhost.com/KB/a694/publishing-your-sql-2008-database-to-Winhost-sql-2008-server.aspx