Hi thekid89 & welcome to Seven Forums
Unfortunately you're setting your self up for a fall by not clean installing. I know it's easier and quicker to upgrade but there really are less headaches this way.
Anyway, checking the startup tab in msconfig and unchecking/disabling any unnecessary items is a good place to start.
The HP Support Assistant thingy is probably redundant on your machine now as it was probably for your OEM Vista.
Keeping a close eye on the 'Rescource Monitor' to narrow down what is causing the CPU spike is also worth mentioning. That way, you can filter the process and see any associated handles,services & modules to further narrow it down.
Resource Monitor