Popularity among kids party themes would depend on the age of the child and usually the gender of the child. Here are some great ideas for your little one's party: http://www.awesome-kid-birthday-parties.com/birthday-party-supplies-for-kids.html
Ideally, the bridal shower would be held 1-2 months before the wedding, but there is nothing wrong with it being held more in advance, or less, provided that the bride can attend.