I'm not too keen on the short plaid skirt only because I'd hate to bend over and flash everyone behind me. However, I think it would be ok with a pair of very thick black tights or even some leggings.
I did come across this plaid trumpet skirt from Rampage.com that is a more acceptable length - especially for the office...
I also like the velvet blazer. I don't think you can ever go wrong with a blazer no matter what material it is made of. It's such a versatile piece. I found this Chocolate Velvet Blazer from Shop.com and fell in love with it! Hmm, it would go good with the skirt, eh?
No matter what pieces you pick for this fall, remember to create a style of your own and of course, accessories are key in putting the look together!