In a food processor fitted with a metal blade, pulse cookies until they resemble fine crumbs, then add melted butter and process until combined.
Transfer Oreo crust to a 9" springform pan and press in crust until firmly packed. Freeze until firm, at least 30 minutes.
When ready to serve, remove springform pan and scoop ice cream over tart. Drizzle with cookies 'n creme bars and chocolate syrup. Slice and serve. (If the ice cream seems too soft to slice, freeze 10 minutes to let it firm up.)