"Looking at the Views Settings tab, you'll notice two subtabs, Basic and Advanced. Select the advanced settings tab by clicking on Advanced to show the following display:
Views advanced settings
Let's look at the Advanced tab first since you'll probably never use these settings.
The first option, Disable views data caching, shouldn't be checked unless you are having issues with views not updating when the data changes. Even then, you should probably disable caching on a per-view basis using the caching setting in the view's edit page in the third column, labeled Advanced, near the bottom ...