Hi, sorry for missing the point.
I have attached a screen shot of my PCs 'All programs menu'. You should have two IE icons within this menu, one marked as 64bit the other not. Clicking on the one NOT marked as 64bit will launch the regular 32bit version of IE.
You cannot set the 64bit version of IE to be your default browser, so I find it hard to believe that Windows is using it by default.
Windows may of pinned the shortcut (for the 64-bit version) to your start menu as you've been using it. Right click on the icon and click 'Remove from this list' to remove it.
If your using the icon on the task bar, you can also right click this and click 'Unpin this program from taskbar'.
Please make sure that all the icons are leading to the 64bit version before removing them.
You can double check which version of IE your currently looking at by pressing the 'Alt' key on your keyboard while in IE, then clicking 'Help' on the menu that pops up towards th top of the IE window, then by clicking about. The screen that pops up will have the words '64-bit Edition' next to the version number. If you cannot see this your running the 32-bit edition.
Sounds like you possibly may be using the 32bit version already, just without the up to date Flash player?
Even though your PC is 4 weeks old (I'm gusessing you bought your PC 4 weeks ago) this does not mean the software on it is up to date. PCs can sit on shelves for months before being sold, your PC was probably manufatured five months ago or longer. To add to that the manufatures don't always load their PCs with the newest versions of software so the Flash version your using could be closer to a year old!
Try going to this link and following the steps onscreen and installing the latest version of Adobe Flash in the 32bit version of IE.
http://get.adobe.com/flashplayer/?promoid=BUIGP
Read the instructions carefully otherwise you'll end up installing the Google Toolbar as well!
If I haven't explained anything clearly enough, let me know and I'll clarify.
Oliver
www.codeblog.co.uk