Abbi -
Can you play YouTube videos? These use flash, and if you can then you would know that you have some version already installed. There have recently been some malicious programs masquerading as flash player, so be sure to download it directly from
Adobe's website.
If you have a previous version, I would think that any decent program would detect that and offer you an opportunity to uninstall it at that time. I just looked in my Add/Remove Programs list, and there is an Adobe Flash Player Plugin and an Adobe Flash Player ActiveX, so I guess you could uninstall these if they show up for you.
Best of luck,
WallyH