A paginated file is one that contains form feeds (ASCII 12).
V will automatically paginate files that contain form feeds, displaying a page marker (dotted line) before the first line in each page.
If you press Ctrl+Shift+Page Up/Down, V will scroll to the next page, but maintain the current position in the page. For example, if you are currently on line 10 of page 1, pressing Ctrl+Shift+Page Down will take you to line 10 of page 2.
Do not enable this option if you want Page Up/Down to behave normally (ie, scroll by the length of the window).
By default, V will increment the line number for each line in the file. If you want the line number of each page to always start at 1, enable the Reset Line Numbers on New Page option.
If you don't want V to paginate the files, select End Of Line->Ignore Form Feeds from the View menu.