I have probably got the terminology wrong. I assumed the panniers was the racking system which carrys the bags.
Have neither one nor t`other. The bike has a number of drilled points on the seat stays. A point where pivot brakes would normally be attached ( bike has vee brakes ) and 4 other similar in the same area of the seat tube. The bike is a Giant Escape 2 if that assists in any way.
Pannier bags (usually just called panniers) are the bags which clip onto your pannier rack (usually just called a rack).
The rack attaches to the bike via braze-ons, in the same way that a bottle cage does (i.e. with a little hex-key bolt) on your bike the braze ons are circled in red here:
I can't make out the lower points from that picture, but it should be pretty obvious when you come to fit it.
As for which panniers, obviously there is a range of sizes and makes for every need.
Altura do a huge range of panniers so are worth looking at, in my experience they are what most bike shops stock.
The "very best" panniers which everyone recommends are Ortileb High Rollers. I have no experience of these myself but everyone raves about them, personally I have some Altura Dryline bags which I think are very good, I have the larger version of these:
http://www.evanscycl...annier-ec008429
That size would be enough for a "short tour" in my opinion, but the best way to judge would be to go to your bike shop and see if they have any and what you think of them.
As for which rack, I have this which is a pretty big sturdy rack, you can get ligher ones, but what I like about this is that it has two sets of rails at the top, so the panniers go on one, and there's another for mounting stuff on the top:
http://www.evanscycl...r-rack-ec006628
here's a picture where you can see my rack and how it's mounted:
hope that all helps.