I'd check into what 715 posted above, about your pre-installed OS having a back-up partition on the HD.........
also, as Skuzzy posted, Windows 7 being just released for public beta.......some hardware, software may have driver issues...alot of people been having some luck using "their vista drivers" in these instances........also you can do a search ( google ) for Drivers or modded drivers for your particular Hardware/software to work with Windows 7.........
I know I went and searched/collected alot of my needed drivers before I even thought of installing Windows 7 RC 64 bit.....
those PC geeks are pretty quick when figuring out workable solutions for new OS / Driver issues....... just check & read the Windows 7 forums ( several of them out there on the web )
Also, if you get one of them nasty Virus' , that is loaded into your memory......it really doesn't matter what you do to try and get rid of it..........BUT- Trojan Remover (whatever the new version is # wise ) is pretty awesome in swiping one of these nasty viruses
Good Luck
edited: agree with humble ......most of my stuff picked right up...I have not installed Aces High yet, though.....but prob will since you say it is working for you.....( will Aces high work on a 64 bit OS? )