No that's not a good idea at all. The fact that Spiritomb has no recovery outside of Wish Support (you can't Wish to this Pokemon while you're trying to utilize your strategy since you have to switch out to do that) means it will get worn down and killed before you manage to do anything significant to your opponent. Trying to lower PP in order to win a game is simply a horrible idea. Spiritomb's low speed means that if the opponent wants to Toxic you, they will do so before you manage to use Imprison. Trick Room only allows Spiritomb to move first three times if you switch it in directly, and besides, Trick Room + Wish is a hell of a lot of support for a mediocre Pokemon using an awful set.
When considering a niche defensive Pokemon like Spiritomb for a stall team, you should think to yourself "What specific threats will this Pokemon be able to beat, and what is the most effective way I can beat them?" For example, Spiritomb's can run a Pursuit+Sucker Punch set in order to trap/kill Psychic types like Jirachi and Alakazam, and its access to Will-o-Wisp + its typing allows it to also check various Fighting types like Lucario and Mienshao. Or, it can use its decent defensive typing and respectable natural bulk to pull of a physically defensive Calm Mind/Rest/Sleep Talk set and act as a win condition.
TL;DR not viable at all because it accomplishes nothing specifically, use the Viability rankings and analyses to see the different good sets a Pokemon can use.