LogMeIn is a powerful tool which can be used to control a remote PC from anywhere as if it is your own system.It offers layers of security which is not there in its competitors like end to end 256-bit encryption,dual authentication and RSA SecureID etc.
LogMeIn works fine even in low band width dialup connections. You will have to create an account in the LogMeIn site and add the computers which are to be controlled into that account. If you does not have a LogMeIn account it will be created in the installation process itself.
The greatest advantage is its hastle free configuration and ease of use. The program differs from its competitors in that the application runs in your Web browser. If you're running Firefox, it asks to install a plug-in and then opens an emulator of the remote PC in a new window.
Download the user guide.(PDF)
TeamViewer is another fast, simple and user friendly solution for remote desktop access over the Internet. All applications are in one single and small module of just arount 1.8 Mb size. It can even work without installing the software in any of the systems as there is a run option in the module. It supports File transfer,Chat and more. Immediately after installing or running the team viewer, it will assign an IP address and a password for your computer. You can share the desktop by just giving these details in the other system. Team viewer may not work nicely if the band width is very low as in case of dial up connections.
Download Team Viewer