When using Vista the "default" profile that you log on with has Administrative rights (protected though by UAC) already. However, if you want to make sure you can always navigate to Blink in your Programs list and right click on it and select "Run as Administrator". Either way UAC, in Vista, will normally prompt you to allow certain actions that Blink attempts to perform.
By default, the first profile you log on with (in Windows XP) also has Administrative rights (unless you later on change these).
Personally the only times you really need Administrative rights when using Blink are to be able to install, remove, update it, or install or transfer its license. Everything else can be done on a limited user account.