Do you have a backup of your wallet.dat and config files anywhere?Here is what I would do, but I'm no expert either, so do it at your own risk -
this is why everyone should backup wallet.dat often. 
copy the entire %appdata%/roaming/Sagacoin directory someplace else. Now, delete the whole %appdata%/Roaming/Sagacoin directory.
recreate the folder, add your wallet.dat and conf files if any.
Start the wallet qt.exe again, see if you can open your wallet and let it resync.
Edit- This can happen if you do not shutdown the wallet when you rebooted. You should always shut the wallet down clean before reboot.
I have idetified the %appdata%/Roaming/Sagacoin directory and I see wallet.dat has the date time hour and seconds of when (day, hour, minute and secons) I just exactly closed the wallet before reboot the laptop.
Would this wallet.dat (saved automatically when I closed the wallet) restore the wallet?, I assume i have to re-install wallet ans the replace these file (wallet.dat, before reboot and sagacoin.conf) into the new created %appdata%/Roaming/Sagacoin directory
Would be?
Thanks!!!!