Upgrading wireless router, need advice

Hey guys. I have an old-ish D-Link DI-524 (well actually a 624, after i flashed it :-P )running my wireless network at home. In terms of speed, its not much of a problem since all i do with it is access the internet and my internet connection at home doesn't come close to its 54mbps upper limit. Range isnt an issue either, although i only get two bars in my room it never drops the signal solely for that reason. The problem with it that i have is that when all three laptops and one desktop in my house are using the internet through it, the thing starts dropping the connection left right and center.

So i wanted some advice on what to get for a new router. Am i right in thinking that any Wireless-N certified router will fit the bill? Meaning, will even the cheapest Wireless-N router surpass my 524/624 router in terms of speed and range, as well as be able to steadily hold more connections? I know there is much more to wireless router performance than just being N-certified, but like i said before range and speed are non-issues if any N-router is faster/has a longer range than my current one, i just need it to not drop the connection like my 524/624.