Did you clean install Windows 7? What are your specs? You need to give us more info to work on.
Anyway, Windows 7 is basically Windows Vista, it will use a lot more resorces than XP, if you are unhappy with the speeds go back to XP, you can try configuring msconfig (Start > Run > msconfig.exe) to stop so many programs starting up with the PC, but otherwise there is not a lot you can do, you could get more RAM, this would make the PC faster too.
Went from a dual processor XP machine to a quad processor Win7 machine. Sure the new machine is faster, but not appreciably so. I use Diskkeeper every night.
Thanks for any help!!