Is it like taskbar has become freezed???
Try one thing!
Start ur windows in Safe Mode and check whether the taskbar problem still exist, cauz its possible that some s/w is forcing taskbar to remain freezed.
Then type msconfig in Run dialog box and goto: Startup tab, and see is there ne undesired s/w listed in the list.
If its there, then simply uncheck it and restart ur windows in Normal mode.
May be it can work...