It's possible that your phone is to blame for the hangup on phone ring. DSL operates using sub-audible signals over your phone line. If your phone is old or poorly made, it may emit signals in the general range of the DSL modem. Putting DSL filters between your phone and the line may help prevent this interference.
Regarding DSL modems, I've found the 2Wire brand devices work exceptionally well. But they only work for AT&T connections. My dad worked for AT&T (well, first it was Pacific Bell, then Southwestern Bell...) for many years, and for the last several years he was the DSL installer for our area. We always had the 2Wire devices (which are usually the more expensive options you purchase from AT&T. Around $100 for the device. It replaces most routers as well though because the 2Wire, in addition to being a DSL modem is also a 4- or 5-port network switch and a wireless router.
You don't usually interact with the control gui of the modem. An HTTP gui just means that in the case you need to set up your wireless or manage a more complex firewall option, you'd log into a page hosted on the modem itself to make these changes. They're generally as easy to use as an online banking page, in my experience.
ADSL2 is a collection of technology standards that allow higher throughput speeds on DSL. DSL is really the slow child of high-speed internet. Some of this is due to the fact that it usually has to run over old copper lines which were meant for analog telephone signals, not digital data signals. ADSL2 is supposed to help bring it into a more competitive system by at least addressing the protocol standards and such.
If you're on an old copper connection, you may want to look into an ADSL2 modem. But if it costs a lot more, I would not consider it enough of a requirement to pay a premium for it. More of an "it's nice if the device has it, but not a problem if it doesn't" sort of factor.
Do you have a DSL filter on your phone line? This may be able to prevent the disconnects when the phone rings. – music2myear – 2011-08-09T21:46:38.670
If the phone frequency is not properly filtered from the DSL frequency, your splitter might be the culprit. – karatedog – 2011-08-09T21:46:41.597
@music2myear everything is properly filtered hence why my old/current one is stable – None – 2011-08-09T23:16:36.977
What is the current setup? The 10-year modem with the new AC adapter? What is the manufacturer and model number of these modems? Are you positive that the replacement(s) are the same model/version as the decade old modem? At the xDSL company I used to work at, new versions were designed every 3 years. – sawdust – 2011-08-10T01:38:43.987
@sawdust: I'm to lazy to actually look but the two replacements were about a month apart and were not the same model (maybe not even same brand) as the older solid modom. – None – 2011-08-10T02:16:54.780
Cisco is still lagging behind, and you can learn more here: https://www.networkworld.com/news/2011/030411-ipv6-home-routers.html
– Teknophilia – 2011-09-25T20:51:49.667