Whenever I try to select a team the game crashes, and I cannot create a new one because the instant I click on the team I want or "create team" button it crashes. Any ideas? :(

To sum it all up, whenever I try to start a game it crashes I suspect it has to do with the teams

Try reinstalling, if there's a problem with the team file that'll fix it.

teamED may be able to rectify the issue.

Try reinstalling, if there's a problem with the team file that'll fix it.
-_- Re-installing might fix the problem. The better choice would be to fix the problem directly. It seems your team file is likely corrupt. I would recommend you delete it and start a new one.

Locate and delete "WG.WWP" found at "...Worms World Party\User\Teams". A fresh, new, working team file should be created for you when you create a new team.

I thought that deleting the team file might have some ill-effects so I thought it best not to go there.
Plus I couldn't remember what the WWP team file was called :p.