You can manually re-order them by using "quick edit" to change the dates. There are several plug ins such as "PostMash" or "Post Types Order" (does pages too). The plug ins make it easy as drag and drop.
You may also want to use "Sticky Post" which allows you to keep one or more posts at the top of the page regardless of order. If you sticky more than one then the date order decides which one is on top. I use Page Order on some WP sites which has a box in quick edit to assign an order# to pages. I find it easier to deal with than the flash or java drag & drop interfaces. They can be buggy at times.
Thanks, Just, I tried to use one of the plugins you mentioned and couldn't work it. So now I just changed the date and it worked fine!
