Best table design for application configuration or application option settings?

I need to store a series of configuration values in a database. A couple ways I thought of to store them are: a table with 2 colums(name,value) and a row for each pair, or a table with a column for each config parameter and 1 row? With the first I only need to add another row to add a config value, with the second I need to add a column to the table. Are there any issues with either I should take in to consideration? Is one more efficient than the other?