my understanding is that no matter what you need a slot2 ram pack to cache the jpgs and whatever else. i know there is a hack to allow the rom to boot without booting the ram first. if you are serious about web browsing on your nds pick up an ez 3-in-1 from dealextreme for 19 bucks (w/free shipping). you can use rudolph's tools to boot the slot2 ram and then softreset back to your r4 menu to run the browser.
before you spend 20 bucks just for ram, please be aware that web browsing on the nds is slow as hell. after a few times using it, you will stop using it. i only check my gmail on it now when i'm somewhere with free wifi and i don't have a pc.
-another world