Rodger,
Being able to run in safe mode, but not in Normal mode is indicative of a missing or corrupt driver - those files that help your operating system interface with your hardware. Safe mode loads the least amount of and most basic types of drivers. It could be something as simple as a video or sound card driver, or something more complicated. Troubleshooting would involve, while in safe mode, "uninstalling" one component at a time, "re-installing" it, then re-installing the component driver (it's possible to "roll-back" drivers to a previous version, but it doesn't sound like you've changed any recently), and finally restarting the machine in Normal mode. You have to do this for each driver, and it could take a while, and still might not be successful. That's why it would probably be easier and faster to slick the drive and start over.