I thought I'd post on here as I have the same issue and may have found a solution, but I have yet to test it because it's my friend's VAIO TZ laptop. This is what I found, I hope it helps other people!
The fingerprint scanner is not related to Vaio Services, it's controlled by the UPEK Protector Suite services. Vista doesn't provide native support for fingerprint scanners, which is why under Vista you need both the UPEK vista driver and the UPEK Protector Suite software.
Windows 7 now has a biometric platform built in for managing fingerprint scanners and the like (type \"biometric\" into the Start menu search box), but it needs an updated UPEK driver to integrate properly (the Vista one is therefore not suitable). Upek have provided a new preview Windows 7 driver for many of their laptop fingerpint scanners that allows basic fingerprint functionality in Windows 7, but they also provide an updated Protector Suite 2009 that wil give additional functions (such as password bank, page registration in IE8 and Firefox, etc). Available here.
The Windows 7 driver doesn't yet work on my SZ3VP however, either using the Windows 7 utilities or the Protector Suite 2009 utilities. UPEK have promised future support for all fingerprint scanners. So for now I've gone back to using the Vista driver and Protector Suite 5.8.
Maybe those of you with newer SZ models will have newer fingerprint scanners and the new drivers will work.
EDIT By the way, the basic UPEK Windows 7 driver (without Protector Suite) should allow for logging in with the fingerprint scanner. Which is all I really use it for anyway