Slow internet connection with 2tb time capsule

Hello I just got a 2 tb time capsule to replace my old lynksys router. I run an apple tv, 2 iphones, 2 ethernet connected win 7 desktops, an iPad and an ASUS laptop running win 8. cable modem is a RCA model dhg536. The internet is much slower with this configuration. What I notice is a significant lag loading web pages and delays and failures to load when using features on web page (example on yahoo mail hit "compose mail" and connection times out). Occaisionally my machines fail to see the internet at all telling me they are getting a "DNS error cannot resolve host (I think that was it)." Strangely streaming does not seem affected. I can watch movies on my apple tv and view things like you tube and apple movie previews without a problem or lag, once the page loads which takes a while. Things I have tried: power cycling everything which fixed the time capsule's ability to see the internet the couple times it completely lost it. I looked into updated the firmware of the rca modem (which is stretching my computing abilities) and it seems to be running the lates firmware, in fact, if I am reading the interface correctly (quetionable) it looks like comcast pushed out an update around the same time I replaced my router.

Another interesting thing I noticed. I was working on this issue using the windows 8 laptop while looking at the airport utility on my ipad. When I typed a new url into my web browser (chrome), while it was taking to long to load the green indicator on "internet" in the utility turned amber while the green symbol by time capsule remained. When the internet indicator went back to green the web page loaded shortly thereafter. Thanks for any and all help!!

Jeremy