Actually the difference between WP.com and WP.org is covered in the FAQ.
edit: Note that Plugins are also covered already in the FAQ. I was going to put it in there now but I see I already did. (I thought I had.)
My issue is most of the questions I answer here (I'd say about 90% of them) would be answered either by a simple search by the asker or is already answered in the FAQ. That's how I find the answers. :) Also there seems to be a great many questions asked that could be answered by having the asker just try the method they propose. (ie the "Can I do this?" questions.)
Please remember I do semi-professional webhosting. I do not get anything out of helping you folks. (Not even BBQ sauce!) I don't mind helping you folks but I seriously think most of you folks should be helping yourselves and I don't see that happening.
Now, if you all want to sign up for my "Soccer Mom" account, I charge $19.95 a month. All you do is send me an email and we do everything for you. Scan pictures, make posts, chnage themes, etc. Have about 50 of them out of 2,200....