Your current card is too hot to just remove the fan. General rule of thumb - the more high end a card was when new, the harder it will be to cool. Of course newer high end cards will always be the hottest.
I would have two recommendadtions:
1. Just get a radeon 9550 card. They're cheap as dirt, but equivalent to a 9600pro in 3d performance, putting them not far less than your 4200, and probably better in some games (not that games apparently matter here). That chip was the best of its generation in performance/watt, meaning it runs cool. Most are passive, but make sure. Of course there are other cards that would be similar, but I like these for the above reason. Get 128Mb, it may help.
Whatever you get, if you are spending more than $40-50, you are throwing it away if you are not doing gaming or 3d rendering/CAD.
2. Passify your old card. If you were junking it anyhow, there's nothing to lose. You may have an old heatsink from a P3 or similar lying around, if not, you can probably get one free at a local shop. Aliminium cuts easily with a cheap metal blade (hacksaw, I've seen those at dollar stores for less than $5 if you're not the sort that has tools around. Cut the corners off the heatsink to clear the components on the card. Put thermal paste in the centre of the GPU, and a tiny dab of super glue on each corner, then hold it together for long enough for the glue to set.
I did the above on my 8500 and ran it passive for years with no problem. AFAIK, the guy I sold it to is still playing CS on it to this day.