large bookshelf and floorstanding speakers require a decent amount of power to drive. your average under $100 equipment just is not going to work very well.
we personally use one of these
http
/www.amazon.com/Sony-STR-DH540-Receiver-Discontinued-Manufacturer/dp/B00BHC7ZT4 which we bought for $200 new. it pushes out about 100w @ 8ohms so is about where it should be for power. it has tons of hdmi and other connections and supports up to 5.2 systems which means its upgradeable. not a bad deal for the price. since its only about $50 more than the stereo receivers (below) it makes sense to get unless you know for a fact you will never use the features like hdmi, optical or upgrade to a surround set.
most 5.1 or 7.1 receivers in the $200 price range only put out 50-70w which while it would work is going to be less than ideal and might struggle a bit at higher volumes.
also of note are stereo receivers (such as below). the problem is that many do not support hdmi and some dont support optical. this means upgrading or using such a system with a tv or other tasks is going to be a no-go. they also arent upgradeable to a bigger surround sound set in the future and basically need to be replaced at that time. your call whether or not they will work for your needs but hdmi or optical will give you the best sound (unless you have a good soundcard)
there is a 2.1 model
http
/www.amazon.com/Sony-STRDH130-Channel-Stereo-Receiver/dp/B006U1VH2S/ref=sr_1_1?s=electronics&ie=UTF8&qid=1411853486&sr=1-1&keywords=2.1+receiver also available which is cheaper but has almost zero features which makes it not very upgradeable.
another one
http
/www.amazon.com/Yamaha-Natural-Stereo-Receiver-R-S201BL/dp/B00F0H88SY/ref=sr_1_3?ie=UTF8&qid=1411853948&sr=8-3&keywords=2.1+receiver with similar lack of hdmi and optical meaning rca connections only and it relies on your soundcard or onboard. as with the previous it would be best with a good soundcard.
most receivers in the $200 price range dont offer
likewise you can avoid receivers completely and just get an amplifier, however for under $200 you will be hard pressed to find anything half decent as you will find only pyle and other cheap brands. these often are rated much higher than they can actually perform and have horrible distortion at higher volumes/wattages. most of your big names in audio really push for receivers or stereo receivers on the cheap end so if you're looking for just an amp it may be worthwhile to get a stereo receiver like the above two instead.
my personal preferences however are for a receiver with hdmi, optical and all the goodies like the strdh540 since if you ever change your mind about what you need to use the system for... you could always use it for another task. for instance if you added 2 bookshelf rears,a center channel and a subwoofer you'd have a nice living room set in a few years. if you went with a stereo receiver its always going to be just stereo and have connectivity limitations.
your call of course.