Assuming you want to save the e-mails, contacts, etc. in your personal
folders (PST) you can:
(1) Use the PST Backup tool provided by Microsoft.
with Outlook open, select <file>, <data file management> and <tell me More>
this will bring up help and the first suggestion "Backup Outlook data with
the Microsoft Outlook Personal Folders Backup tool" will walk you through the
process.
(2) Or, with Outlook open, select <file>, <data file management> find where
the .PST file is and save it somewhere else and then once outlook is
re-installed, use that folder as your .pst.
(3) Ask someone who has done it to do it for you and take notes.