Windows 7 Windows 7 has been a disaster for me

I bought a new HP laptop before starting graduate school this fall. After hearing a lot of murmuring about vista I made sure to buy after the deadline for free windows 7 upgrades. Dispite all the hype the 7 upgrade has wrecked my laptop;s battery life and performance. The battery lasts half as long and the machine is putting off far more heat and taking longer to perform tasks. Why am I having such a hard time? I really depend on this computer for school and I don't know what to do. Can I go back to vista?