i tried upgrading my desktop and device software, and now my BB is all messed up. my DTM will not open up. i can't sync to my computer and all that.

when i click on the properties for my device manager it, says this:

BlackBerry Device Manager 4.2.1.9
BBDevMgr 3.1.0.1
RIM USB Driver 3.1.0.1
RIM USB Serial Driver 2.1.0.3

someone please help.

Tell us what you did and how you did the upgrade - over the air or via DM.

Sometimes, simply re-installing the Desktop manager will work wonders.
Try that first.