Never use one lookup table for everything. It will make it more difficult to find things, and it will need to be joined in every query probably multiple times which will mean that it may cause locking and blocking problems. Further in one table you can't use good design to make sure the data type for the descriptor is correct. For instance suppose you wanted a lookup of the state abbreviations which are two characters. If you use a onesize fits all table, then it has to be wide enough for teh largest possible value of any lookup and you lose the possibility of it rejecting an incorrect entry because it is too long. This is a guarantee of later data integrity issues.
Further you can't properly use foreign keys to make sure data entry is limited only to the correct values. This will also cause data integrity issues.
There is NO BENEFIT whatsoever to using one table except a few minutes of dev time (possibly the least important concern in designing a database). There are plenty of negatives.
