Inspiron freezes in Windows 7 upgrade

I purchased an Inspiron with Vista last year(sorry I don't have the model # because the computer is at my store) and kept it in the box until I had the money to purchase point of sale software for my business. I was finally ablee to afford the software in July, but the software maker recommended that I upgrade from Vista to Windows 7before I installed their software, which I did.  Almost immediately after I installed the software and started entering my inventory, I started having problems with the computer freezing at random several times a day.  This was usually resolved by hitting CTRL-ALT-DEL, but once in a while I would have to do a hard reboot.  From reading these forums, it seems I might have to upgrade my drivers.  It was also recommended in another forum that I do a clean install of Windows 7.  Any suggestions or advice would be appreciated.