I've used both VNC and PCAnywhere.  I use VNC to control my iMac at home behind a firewall from my PC here at work.  That way I can test whether or not the webpages I design work on Macs (I'm a web developer/Java programmer).  I use PCAnywhere to control my work PC from my laptop.  I usually VPN in to work's network, and then connect to my PC to do software builds and transfer files that I work on at home.  
PCAnywhere has crashed a couple times on me (which means a trip out to work to reboot the computer) and VNC isn't too stable on a Mac.  I doubt it ever will since they're no longer doing any work on VNC.  I like PCAnywhere though since it has more options for encryption and security.  Both sound like they would work for you.  One other note, VNC is free, PCAnywhere is not.