Template:UpdatingScriptsAndWebApps

You'll need TortoiseSVN installed and the repo checked out.

Make a batch file and put it somewhere reasonable and include the following:

svn up "<local path to the repo you checked out>"

for example:

svn up "C:\Program Files (x86)\ISoft Data Systems\PrintQueue"

Then create a Windows scheduled task with two triggers, one that runs at a reasonable time (probably late when no one is using the system) and one that runs at system startup.