What are the differences between the Baptist and Pentecostal denominations?

The Baptists and most Pentecostals believe the same on the basics of the Trinity, etc., but the Pentecostals lean more toward the gifts of the Spirit and Baptism of the Holy Spirit. They are open to the Holy Spirit in a different way than the Baptists are.
There are many good Baptists who show gifts of the Holy Spirit in their lives but they just express it in a different way. Openness to the Spirit is an individual thing that does not necessarily travel along denominational lines but rather entails the obedience of the person involved. God doesn't care what church you belong to, whether Baptist or Pentecostal, but what he is interested in is whether you are humble before him and obedient.  

 

 

Another answer:

Pentecostals believe in speaking in tongues, raising their hands during worship, etc. Many Baptists do not. Also, many strict Baptists believe that contemporary music is wrong, women must wear dresses and dress modestly, and the King James Version is the only true Bible translation.    

Another answer:

Baptists, at least in my country (New Zealand), are very diverse. A good many of them do believe in speaking in tongues and other miraculous workings of the Holy Spirit, though they wouldn't usually emphasize them to the same extent as Pentecostals do. I have known many Baptists who speak in tongues, for example, but I haven't met any who would make that a test of fellowship.
From personal knowledge, some Baptist churches in my city allow speaking in tongues during the worship and some do not. Some of the more conservative Baptists, who are unhappy with speaking in tongues, have formed breakaway groups (Faith Baptist, Bible Baptist, etc) in protest against the official tolerance shown by the Baptist Union.    

Another answer:

Also, not all Pentecostal churches are as liberal as others. Ours, which is a Foursquare Church, is more conservative even though we do believe in speaking in tongues and it happens once in a while, and it is done in a "decent and in orderly manner" as the Bible teaches to do. I have been in churches where this was not the case, people jumping over chairs during the sermon etc. and it was a big turnoff.