I've installed and use VB6 for legacy projects many times on Windows 7.
What I have done and never came across any issues, is to install VB6, ignore the errors and then proceed to install the latest service pack, currently SP6.
Download here: http://www.microsoft.com/en-us/download/details.aspx?id=5721
Bonus: Also once you install it and realize that scrolling doesn't work, use the below: http://www.joebott.com/vb6scrollwheel.htm