WebSnapshot allows you to make snapshots very easily.
Enter the Url and Press Snap. Or Drag&Drop it from your browser. Click on the Thumnails to Save. With Auto Save Checked, the thumnails are immediatly saved to your 'save' folder.
Select the type of Snapshot you want to make: Thumbnail, Browser size, or Full Page.
You can tailor the way the snapshots are take in the Preferences pane. Set the download folder as needed. By default the snapshots are saved to the Desktop.