You can simply download the 1.7.1 tarball and upgrade in one step. The Links, Polls, Spam-X and Static Pages plugins come bundled with Geeklog and will be updated in the process.
I would disable the other plugins before the upgrade and then re-enable them afterwards one by one to see if any of them causes problems. For the Forum plugin, there's a newer version (2.7.3) in our downloads area.
Note that if you're using a custom theme, then that theme will have to be
updated. I'd suggest switching to the included Professional theme for the upgrade process.
bye, Dirk