problem booting Win98 after instralling

My problem started on Sunday 1/2/00. I installed Tweakui but I think I installed the wrong file, now I boot the PC & it does the regular stuff @ boot time but when it’s time to load windows interface it locks on me, I don’t get anything but a color screen the color screen is part of the win98 interface. The task manager is there but with programs that I have installed 6 months ago, no systray, no Rnaapp ( nothing.)
I think that I have a REGISTRY problem. The file I installed was TWEAKUI,cpl or the TWEAKUI.cnt I am not sure of the file I installed, but I can’t get none of my Icons, Taskbar, nothing just a color screen with the mouse, no Win98.
Help