You can but it will also open it up so that others can get into it too. You need to make sure that all accounts on your home computer have strong passwords. Also, more than likely your company network has that port blocked. remote desktop might work if you are using XP pro at home IF your work doesn’t have that port blocked too. On your home computer you would have to right click My Desktop icon on the desktop and go to Properties. Then in Properties go to the Remote tab at the top. Then put a checkmark in “Allow Other Users to Connect Remotely to This Computer” and choose which accounts you want to let in.
You would want to install something like sygate personal firewall, (free), at home to make things more secure. than in the applications section of sygate only allow connections thru from the MAC address of your work computer.
Then if you have a router to block traffic coming into your home network like a netgear cable/dsl router that uses NAT, you can port forward the Remote Desktop Protocol port, 3389, to your internal computer. You could even get more complicated and use IPCop, (free), on an old computer to use as a router that will log all activity in and out of your home network so that if someone does get in you have logged proof of who did it.
Another thing that you will need is either a static IP address or a dynamic DNS for your home PC. Otherwise, there won’t be a consistant way for you to connect to it.