For those who couldn't easily find the instructions on how to upgrade Joomla 1.6 to Joomla 1.7 and have an earlier version install than Joomla 1.6.5, here's how ya do it.
First download the patch file for Joomla 1.6.0 to Joomla 1.6.5 from here. Then upload it to your Joomla installation's root and unpack. Then you can follow these instructions to upgrade to 1.7 (basically use Joomlas new one click update feature to upgrade).
This will work for Joomla 1.6.0, 1.6.1, 1.6.2, 1.6.3, and 1.6.4.
If your own templates are not customized standard Joomla templates with the same name, then you should be okay. However, if you made changes to Joomla's default templates, you should follow http://docs.joomla.org/Customising_the_JA_Purity_templateto create your own template based on the default one so that upgrades, etc do not overwrite your changes.
How to save my work I did till now ??
It might be helpful to mention that these files will replace the existing files in the web root directory just in case it isn't obvious to other visitors. Thanks again!