how can i delete unwanted software

Many vendors supply "uninstallers" - before just trashing an application, check the developer's website for instructions on how to properly uninstall a given application.

For apps that do not have uninstallers, you can always try something like "AppCleaner" (free) to uninstall the app and any auxiliary files it may have generated. Be very careful i using such a program - before you send all of the files to the trash make sure that they're associated with the application. Sometimes you simply won't be able to rid your system of these auxiliary files - but AppCleaner can help. Just be careful.

NONE of the applications that purport to 'clean' your Mac are of any use - and many can seriously damage your system. Stay way from them all.

Clinton

I use a wonderful and free utility, EtreCheck, to determne what is installed on my machine and what possibly problematic starrtup items, launch daemons, launch agents, kernel extensions and such are installed on my machine. EtreCheck show you by category what is on your machine and provides links to the vendors where you can look for uninstallers and vendor forums that have further information. EtreCheck also shows you the directory path where items are stored so that you can navigate to those areas and remove those items that you are comfortable removing.

When I started using EtreCheck I not only discovered software I didn't want, but also remnants of software that I had installed years ago and thought was fully removed.

EtreCheck is a product of EtreSoft. You can find more information at their web site: http://www.etresoft.com/etrecheck

I always do an image backup of my system using either SuperDuper or CarbonCopyCloner before removing things so that I can go to the backkup image and put things back if I delete a file by mistake.