You came to the right place! I know someone will give you the details on how to do the job.
Generally, you have to be careful with lifting the car safely. One of my best "tool" investments has been a set of heavy steel ramps to drive the car up onto for service. While jackstands are a huge safety improvement over critically unsafe regular jacks, the ramps are even more stable when the car is correctly driven up onto them. They usually provide more clearance too.
Also, what I really wanted to quickly pass on to you is that from what your situation sounds like, you really don't want to drive the car until this problem is fixed. If the driveshaft should actually come loose and fall down, you're looking at a major problem - destruction of the driveshaft and nearby parts.