Here are answers to your questions:
1. You need to edit the BlogPosts control (see attached screenshots):
- click Edit, in Basic tab click on number 3 (Settings) [-> see BlogPosts_Settings_link_1.png]
- scroll down (green color in BlogPosts_Settings_Change_2.png). Uncheck the fields (yellow) you want to exclude in both sections (red). [-> see BlogPosts_Settings_Change_2.png] Note that you need to uncheck the fields in both sections because the first section contains settings for the whole page that displays blogs while the second one contains settings for each blog item.
2. Unfortunately, you could not use social bookmarks in Sitefinity without upgrading to v. 3.2.1616 . Let us know if we could assist you in the upgrading process if you decide to do that.
Hope this helps.
All the best,
the Telerik team
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