Short answer? You can't.
Joomla! 3.2 is considered an end-of-life release. Due to lack of adequate information in the Joomla! XML update stream Akeeba CMS Update can't automatically know that 3.2 is the last version supported on your server and can only give you the option to install the latest and greatest version.
Speaking of PHP versions: what the heck is your hosting provider smoking?! PHP 5.3.7 (the minimum requirement for Joomla! 3.3) was released on 18 August 2011. This is nearly 3 years ago. In computer terms this is, like, a century ago. It has been superseded by over five dozen PHP releases in the meantime. In so many words: even PHP 5.3.7, the minimum requirement of Joomla! 3.3, is desperately old and abysmally insecure (not to mention unbearably slow). Would you drive in a 100 year old car that hasn't seen the inside of a mechanic's shop for five decades on the freeway? Because this is what you're doing with your site.
My sincere advice: ask your host –no, demand from your host– to install and activate the latest PHP 5.4 release. Anything else is insecure, slow, obsolete and simply not suitable for running a production site.
Nicholas K. Dionysopoulos
Lead Developer and Director
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