Below the Game List are various buttons and entries, and at the bottom you'll find the Database Switcher.
Clicking a game will select it. Select multiple games using Control+Click and Shift+Click. Right-clicking game(s) presents a context menu for various actions. Double-clicking loads a game.
Right-clicking a Column Title allows one to reorder them, or change the alignment.
Quick searches can be performed by entering text in the combo-box and pressing Enter, or clicking the Filter button. Use "+" as a logical AND with the Filter button. For example: "Kasparov+Karpov". Similarly, the entry-box allows finding a particular game by number. Both these widgets will load the current game by pressing Control+Enter.
To see games matching the current position, set 'adjust filter' in the Tree window. For more info about Searches and Filters, see here or below.
The database can be permanently sorted by clicking column titles. Sorting is not undoable, and may affect search and tree performance. For more details see Sorting Database.
Scid has two notions of removed games - which can be confusing.
The first is Filtered Games. In the Game List widget, right-clicking some games and selecting Remove will remove those games from the filter. They will disappear from the Game List, but can easily be seen again by reseting the filter with Reset. Filtering games has no effect on the database.
Deleted games on the other hand, are not removed from the Game List. They are simply marked as deleted, and no further action is taken until the database is compacted - whence they will be permanently deleted from the database. This can be done by the Compact button, or from the maintenance window.
The Game List only deletes (up to) a page of games at a time. Deleting or manipulating ALL filtered games, is also done from the Maintenance window.
The default database (Clipbase) cannot be compacted.
From the Gamelist context menu, one may Browse a game. This is a game preview which displays in a separate window, without comments or variations.
From this preview, one may Merge the game back into the current one as a variation. The merge starts from where the games differ (taking transpositions into account), and you can change the last move number to be merged, according to whether you are interested in adding the whole game or just its next few moves.
The board size can be resized by Control+Wheelmouse or Control+Shift+Left/Right.