In fact, with all modern PCs today, you should use all the energy saving options possible to let your PC running as long as possible (unless you really need to shot it down to save battery when not plugged : but even in this case, it is even simpler and faster to use **hibernation** rather than shutdown and reboots).
The best time to really reboot your system is not when you want to start using it, but when you have finished using it : reboot it, and then leave it reboot on the logon screen and then go automatically in sleep mode. Windows will run many maintenance tasks for you (including the defragmentation of some critical boot files, and some cleanup).
But if you leave your PC constantly off, and just powers it up when you need it, Windows will never be in idle time enough to perform those automated maintenance tasks that improve your performance.
Windows 7 almost never needs to be rebooted, unless you are instructed to do so. Hibernation and energy saving options will definitely be better. If your notebook is connected to a power plug and not on battery, you can instruct it to not hibernate but to use sleep mode after idle time. Windows and antivirus softwares will perform most updates in the background for you when you don't need the PC, so even if you need to reboot when you get out of sleep mode, you can do it : most maintenances will have already been performed and maintenance operations will not start immediately at power on).
CCleaner once a month with the minimum basic settings will make the rest of the cleanup that Windows does not perform itself. (But experiment with cleaning up some optional temp and working/cache files for the various additional softwares it detects that are installed on your system).
I almost never need to reboot my Windows 7 PC's, except after a few critical Windows Updates abount once in a month (Windows will tell you if and when such update occured that requires a reboot : you may still use your PC to do the task you wanted to perform immediately, reboot once this is done, this wil lsave you lots of unnecessary waiting time). Generally there's no emergency to reboot, but you should avoid installing new softwares if your system shows that it requires a reboot to complete any installation.
Even after almost 2 years of use, all my PC with Windows 7 can boot in about 15-20 seconds (there's an additional delay of about 10-15 seconds if your PC runs on a RAID array, due to the RAID initialization time to check the state of the storage array and needed to detect initialize and synchronize all disks in the array, an initialization time that is not part of Windows itself but of the RAID BIOS before Windows starts booting ; there's almost nothing you can optimize in this RAID initialization time performed by the BIOS, it is needed for the stability and safety of the RAID array, even after an unexpected shutdown caused by loss of power).
The only time where Windows takes a bot longer to boot is aftera few critical Windows Updates that requried to reboot. Once this is done, it is best to loose immediately after this boot time some of the monthly manual cleanups (CCleaner, puring the old snapshots, and starting a new full system backup).
Don't loose time just to defragment the videos you just downloaded from the Internet (they are normally on a separate volume and not needed for boot time, so they are not a problem). Just keep your PC on, and avoid most unnecessary reboots (and don't disable all Windows services and scheduled tasks ): if you turn off your PC for long, most scheduled maintenance tasks will only start at the same time at the first boot time...
Once again: hibernate if you run on a battery, otherwise just use the energy saving sleep mode, and your PC will lamost laways be ready to run fast when you need it. At home, leave your PC running during the night, and schedule the Windows tasks to run when you're sleeping (but make sure that you have not let your browser open with many tabs : this will help the maintenance tasks to perform more cleanup)...