Okay so wireless standards started off with 802.11 then it went:
802.11a - 54 Mbps on 5Ghz
802.11b - 11 Mbps on 2.4Ghz
802.11g - 54 Mbps on 2.4Ghz
802.11n - 150 Mbps on 2.4 or 5Ghz
802.11ac - 860 Mbps on 5 Ghz
ac is only in draft mode and most devices won't be ready until 2014. If you buy it, you may then have to buy compatible ac devices in the future to make the most of it and if the spec is changed, you'll have to replace it anyway so not really worth the effort.
A router is designed to send info between devices, and most wireless routers do just that - they connect to computers/ipads/iphones/playstations etc wirelessly and can transfer data. But some come with a built in ADSL modem, some have a cable modem built in, and the rest don't have either.
Your options are to buy just a router and plug that into your Thompson box. The Thompson box connects to the internet and passes the info on to the router which then transfers it around to your devices. It means an extra box that has to have a power socket so I prefer routers that have built in ADSL or cable modems.
If you want to stick with asus, the only one they do with ADSL is the DSL-n55u. That'd be the one I'd buy if I wanted asus.
