Install Service Pack 1 on your system.
Think of Windows 7 as the best Service Pack for Vista.
That is because Windows 7 is basically Windows Vista with a crapload of bugs ironed out.
Think of Service Pack 1 for Windows 7 as a major bug patch which may provide valuable
fixes to your machine which will thereby provide less opportunity for the 3l33t h4x0r.
In short- install the pack as it will fix holes in your system.