I agree that a clean install is a must to get rid of the vista problems. However--make sure you boot to the win 7 disk and select Custom Install before formatting the disk. You must format the disk using the win 7 upgrade disk not a third party utility or you will have problems with activation. MS has decent instructions at the Win 7 help site HERE.  
The machine I'm trying to upgrade to Win7 is a Dell Inspiron 1545 laptop. I ran the Windows Upgrade Advisor.  Its stated that I was 100% for upgrading to Win7.  I am currently running Vista home basic.  I have tried upgrading to Win7 twice now with no luck.  It gets done with all the files, installs, ect.  Then I restarts and says that the upgrade could not be installed.  It then reverts back to vista. I have disabled my Antivirus also during this.  My vista is SP2.  I am really at a loss here because it doesn't give me a reason for not installing.  Should I just bite the bullet and do a complete/fresh install?(Not really wanting to do this) Thanks Tad
Vista to Win7 Upgrade Issues