The exterior of the Curiosity shop is only ever featured within the first episode of Wonders in Letterland (Trouble with T-Bag). The shop is actually called Papillon and can be located on Church Street in Twickenham. The interior shots of the shop were filmed on a set.
Even though Debbie's surname is never mentioned throughout any of her three encounters with T-Bag, she is listed as Debbie Carter on the reverse of the DVD cases for series one and series two.
Wonders in Letterland is pre Jumanji (1995). In the series, Debbie is magically pulled into the 'Wonders in Letterland' board game.
In opening scene in Episode One, if you look closely a Ewok Village playset from the movie Il ritorno dello Jedi (1983) can be briefly glimpsed in the window of The Curiosity Shop.