Hi,
You can simply set A record on your VPS for your subdomain and make it point to your home PC's IP address. You don't need anything besides named/bind service on your VPS. If you have a cPanel VPS, then the named service will be there by default.
If the IP address of your home PC is dynamic, then you will need to install following software on your home PC :-
DynDNS.com - Services -- Ultra-reliable DNS services
There are several other remote access commercial solutions available in the market eg:
pcAnywhere, GoToMyPC & No-IP