Which hotel in Taipei is recommended?

It is quite depends on which kind of shopping you'd like to do.
If you would like to shop in big mall and want to have a better sleeping enviornment, 國聯 is really good! 京華城 & 101 are not far away and 國父紀念館站 is just at the back.

If you want to shop in those little market, small hotel in 西門町 like 長虹、華華、天城 may fit you...they are much cheaper too..

For 四季大飯店, I lived in it b4. I'm highly recommended but if you are considering the shopping area. It may not up to your needs.
四季大飯店 has its own free shuttle anyways to pick you to 台北車站 & 西門町 etc.
There is a little 夜市 (寧夏夜市) just five-min-walking away. & there are DIY shops nearby.

以下是台北市中心的homestay套房；
http://taipeihomestay8.blogspot.com/ 民權東路吉林路口

http://taipeihostel.blogspot.com/ 忠孝東路林森北路口

已經有很多歐美、港、新、馬旅友住過。
大家參考看看囉!

which series hotel do you want? are you in H.K.? if yes, you can go to the travel agency to look, so like 新驛(near Taipei Main Station)or 長虹(near 西門町)is OK. I recommend 長虹 is better, because 西門町 is good for shopping.