Putting the path to Vboxmanage is not difficult as long as one does it carefully. I do it for every host I have so I can just type vboxmanage without the path. Instructions can be found here: http://msdn.microsoft.com/en-us/library/office/ee537574(v=office.14).aspx
The site is for Microsoft SharePoint, but the process is the same for anything you want to add to the Windows path.
Here is what that site says: (Works for Windows 7, likely for other Windows flavors, too.)
To add a path to the PATH environment variable
1.On the Start menu, right-click Computer.
2.On the context menu, click Properties.
3.In the System dialog box, click Advanced system settings.
4.On the Advanced tab of the System Properties dialog box, click Environment Variables.
5.In the System Variables box of the Environment Variables dialog box, scroll to Path and select it.
6.Click the lower of the two Edit buttons in the dialog box.
(Personal recommendation here: Before editing the path settings in the Variable value box, copy them to the clipboard and save them in a notepad document so you can put back what was there if something goes wrong.)
7.In the Edit System Variable dialog box, scroll to the end of the string in the Variable value box and add a semicolon (;).
8.Add the new path after the semicolon.
(You can get the new path easily by opening the Oracle Virtualbox install folder, by default C:\Program Files\Oracle\Virtualbox, clicking in the Address bar of the window and copying the path.)
9.Click OK in three successive dialog boxes, and then close the System dialog box.