Can I delete Metadata files with Ext. .abcdp?

I am using my OS X 10.6.8 imac and in FINDER under my home name there are a bunch of metadata files from my Address Book Card Data. I would like to know if I delete them will my Address Books corresponding files be deleted or will it have any other negative effect. Also, not sure if this is allowed but I would also like to know if I can delete files in a CACHE Folder that begin with com. i.e. 'com.apple.Dictionary or 'com.apple.Automator.CActionCache-2.plist' Any advice would be appreciated. Thank you all and have a great weekend. 😕