Assuming that 2nd one is the Netgear DG834G v2, which is what it looks like, then I've got one at home......works quite nicely, copes with a thousand or so bittorrent-connections without breaking a sweat (probably more, but never tried), and maintains a wireless connection to my laptop at the same time. Never had any problems with it...

The Linksys, first link, looks like it's been superceded by a newer model, but looking at the description, it does have an integrated modem......a microfilter is just the device that plugs into each phone-socket, to filter between ADSL signals and telephony signals.