I wan't to remove my website for some months from DO. Is there is any way that I can download my server Image so that I can re install it after some months. Please suggest if there is another procedure to do this.
DigitalOcean provides a similar feature.
You can take a snapshot of your server (Snapshot → Take Snapshot) and then destroy your Droplet (Destroy → Destroy).
Snapshot storage is currently free, later it'll be 0.02cent/GB/month.
Then, you can build a new Droplet starting from your Snapshot (Create Droplet → Select Image (My Snapshots)), and everything'll be like your old server :)
Else, you can download your web root directory and reupload it when you need, but you'll have to re-configure everything.