I too have noticed Win7 takes longer to boot than other version of Windos.
One way to speed up the boot process is to optimize the BIOS by disabling any settings or peripherals that you do not use. Examples being disable IR devices in the BIOS if you have no IR devices, disable the serial/parallel ports, and set the priority of the bootable disks to make the OS hard drive the first boot device.
You can try running the Performance troubleshooter to find any issues that might slow down your computer. To do so Click the Start button > click Control Panel > In the search box, type troubleshooter, and then click Troubleshooting > Under System and Security, click Check for performance issues.
You can also try deleting programs that you don't use, defragmenting your hard disk, and using Disk Cleanup to delete files that you don't need.
An upgrade to my hard drive solved almost all of my Windows 7 problems, including slow boot times and application crashes. There was no indication that the old hard drive was bad, just a lot of buggy behavior.