This card can target any card on the field, regardless of what type of card it is (Spell/Trap/Monster) or whether it is face-down or face-up.
In general, if you cannot apply the card's effect when activating a card, then you cannot activate it. Thus, if there are no cards on the field that can be destroyed, then you cannot activate "Mystical Space Typhoon" nor a Set "Raigeki Break". Also, when you activate "Mystical Space Typhoon", it cannot target itself.
Mentions in Other Rulings
If a Flip Effect Monster is face-down on the field and is destroyed by "Raigeki Break", then you cannot activate its Flip Effect.
During the Damage Step, in general, you cannot activate Spell/Trap Cards other than Counter Trap Cards and ATK/DEF-increasing/decreasing effects. Thus, you cannot activate "Book of Moon" nor "Raigeki Break", but you can activate the Counter Trap "Divine Wrath" during the Damage Step.
Inferno Reckless Summon: If cards like "Book of Moon" or "Raigeki Break" is Chained to "Inferno Reckless Summon" so that neither player has any face-up monsters at resolution, then neither player Special Summons monsters with the same name. If only your opponent has monsters, then your opponent still Special Summons monsters with the same name, even though you do not have any face-up monsters. If only you have monsters, then only you Special Summon monsters with the same name.
These TCG rulings were issued by Upper Deck Entertainment and have since been deemed unofficial by Konami. They were previously considered official and can still be correct, as long as they follow the official gameplay rules, or unless Konami has issued a ruling that says otherwise. References: 
D.D. Scout Plane: If "D.D. Scout Plane" is face-down on the field while "Banisher of the Light" is in play, and "D.D. Scout Plane" is destroyed by "Raigeki Break", it is removed from play and its effect activates because it is placed face-up out of play.
Peten the Dark Clown: If "Peten the Dark Clown" is discarded as a cost for "Tribe-Infecting Virus" or "Raigeki Break", the last thing that happened was that those effects resolved, so the effect of "Peten" does not activate.
↑Konami Judge Program Rulings are considered unverified, as their source(s) are not publicly viewable. They are not confirmed as applicable to the TCG until they have been officially published by Konami.