It is not uncommon for the registry to grow huge over time, which tends to slow down the computer's startup and makes it unstable. You can end up getting lots of unnecessary personal computer registry entries that are created when you install or remove software program and computer hardware using your laptop. Sometimes an "orphaned" registry entry can confuse Windows 7 during startup and cause a delay. Generally, slimming down your computer registry will make Windows 7 run quicker.
The REGEDIT command will assist you to view and edit the registry, but if you don't know what you're doing under the hood, just put down that wrench and retreat slowly. You can do a lot of damage to your system by flailing about with a registry editor. Specialized programs exist to examine the computer registry, compare what's in there to what's truly on your system, and also correct or delete erroneous entries.
RegSeeker
registry cleaner software REGCLEAN is a utility program incorporated into Windows 95 and Windows 98. This program is no longer officially sustained by Microsoft, but some users report that it works fine on Windows 7 systems. However, I don't advise that it be used on XP, since the structure of the registry is different in XP than it was in earlier incarnations of Windows.
CCleaner is really a highly rated (and free) registry cleaner freeware that I like. RegSeeker is an aggressive cleaner, and in some cases may delete computer registry entries that are required. Some CCleaner users have reported that using a RegSeeker exclusion file can prevent it from making erroneous deletions.
An additional popular free registry fixer/cleaner is CCleaner, which does some additional things like cleaning your browser's temp files and deleting unneeded files. RegSeeker has a status for being less aggressive so may be a better option for non-expert users who wish a totally free registry cleaner freeware.
Uniblue RegistryBooster is not really free (US$2

, but looks like it's the best advanced tool in the class. Several 3rd-party tests have established that it improves both boot time and application launch time. In the past, I've find out about people with problems uninstalling the CCleaner Registry Booster software package after downloading a trial version. To my understanding, the corporation has resolved those problems. If you're a non-techie, I would advise this tool over the others.
There other registry cleaners available, some free and some not. If you would like play the field, read several reviews by reputable sources like CNET or PCWorld before you install. If you're not careful, you will get an adware or virus-http://www.registry1000.com/2010/05/05/microsoft-registry-cleaner---how-do-you-get-the-best-one/ wannabe that claims to do the job, but could have nasty side effects. See my companion article Free Registry Cleaners for many others that have earned good reputations.