Peach/Sheik is top 5, lemmie check my notes.
Ed: top 10; top 5 are Peach/Fox, Sheik/Marth, Fox/Falco, Fox/Marth, and Fox/Puff, in no particular order (fox is too good in teams).
Peach
Sheik - 9/10 Both do solid damage-dealing, and have quick effective projectile edgeguards in needles and turnips and otherwise in their respective nairs, fairs and bairs, as well as both having pretty gay downsmashes. In this matchup, Sheik will generally act as a frontman, being the decoy and opportunist, while Peach constantly spaces and harasses the opponents with float cancels and turnips. The general idea is not to get hurt too much, and keep the pressure on. This team requires a bit of practice, but is both fluid and powerful once you get the hang of it. Sheik's space animal weakness is somewhat apparent here, however, and some losses will come from solid Fox/Fox, Fox/Falco, and Falco/Falco teams who are resistant to the pressure game and can avoid downsmashes; try to have Peach capitolize on the player focusing on Sheik, as almost all of her moves are extremely safe. This team also lacks a solid low % KO finisher and a good grab combo game, so the partners should be VERY experienced at supporting each other's edgeguards and recoveries, to prolong their lives and cut short their opponent's.
This is kinda old, I need to update it, but alot of stuff is good.
Your alternate should be Ganon; Peach edgeguards fuxmazing, so you want a good stock tank that can get people off the stage quickly and kill at low %s, and the double tank power of this team is disgusting, they seriously live for years. If you're having trouble with Jiggs (Aero's Jiggs is most likely just alot better than you guys, Aero is **** good), be patient, have the Sheik handle her, and focus on killing her off the top, because knocking Jiggs off the side is pretty pointless.