There are lots of good reasons to choose to replace radiators with hot water baseboard heat. Old fashioned rads are, let us face it, ugly and spoil the decoration of your home. Not so with baseboards which sit neatly out of the line of sight - no more staring at the radiator while you watch TV!
Hot water baseboard heaters work exactly like the radiators however, so make a good simple upgrade to your home heating system. Unless your radiators are very old you will probably not get a noticeable performance upgrade, but you will get an aesthetic benefit. This can be well worth the minimal trouble involved.
Luckily it is quite a common upgrade, so many baseboard hot water fins are designed to slip in where the ugly old rad was. An easy job for an experienced fitter, and a possible job for a competent home enthusiast. If you are not confident you better leave it to an expert since you really do not want water leaking all over the place!
The main thing is that hot water boilers for baseboard units are just the same as you currently have, so there will be no need to touch any of the fuel system (gas, electricity, oil or whatever). However, remember that modern boilers are significantly more efficient and environmentally friendly than units that are ten years old or older. Replacing the rads may be a good opportunity to upgrade your boiler at the same time!