Help with router DSL settings

[#1]

I have a Tenda TWL548D wireless router/modem that has some unfamiliar settings on the DSL set-up page I would be grateful for some advice about.
Enable Quality Of Service ....Select or not ?
Service Category...I have to select one - default seems to be the selected 'UBR without PCR'
UBR without PCR
UBR with PCR
CBR
Realtime VBR
Non-Realtime VBR
VLAN Mux - Enable Multiple Protocols Over a Single PVC.....currently not selected.
Authentication Method:  (currently Auto is selected)
Auto
PAP
CHAP
MSCHAP
PPP IP extension...currently not selected.
Dial on demand (with idle timeout timer)...currently not selected.
I also found a firmware update for the router but I think I'll pass on that as I can't see how to install it. WPA/WPA2 is already available and it seems to be working fine.
Thanks

[#2]

You can download the user manual from here http://www.tenda.cn/downloads/show.php?itemid=329
Not a router I've seen before but looking at the manual , I'd go through the 'fast setup' , select the country as UK, configure it for PPPOA and just accept the defaults. The manual tells you how to do the firmware update, its pretty close to the end.

[#3]

Thanks for the link to that manual, I had already downloaded it.  It's impossible to select a 'Country or Region' in the 'fast set-up' as there's nowt in the drop down lists !!, - but I pretty much followed my nose and got it connected even ignoring those settings I queried.
Seems to be working fine with Plusnet and a steady wireless connection so I'll not tinker with it any further.
It was a bargain basement item from Ebuyer a couple of years ago apparently and been stuck in a friend's cupboard ever since 'cos he couldn't get it to work.

[#4]

Quote

so I'll not tinker with it any further

Always a good idea, as they say 'if it aint broke, don't mess with it!'