Blasphemy of the Holy Spirit

I came across a site the other day that is against speaking in tongues to the point they say it is blasphemy and since the person cannot understand what they're saying, they may be cursing God.  They believe tongues was done away with, though there is no scripture that ever suggests that.  It's interesting to me that they don't deny all of the gifts but only some...like picking and choosing. 

It particularly caught my attention that they claim speaking in tongues is blasphemy.  Matthew 12:31 states "Wherefore I say unto you, All manner of sin and blasphemy shall be forgiven unto men: but the blasphemy against the Holy Ghost shall not be forgiven unto men."  Jesus was casting out demons and the Pharisees were accusing Jesus of being the devil. 

1 Corinthians 12:8-11 says: For to one is given by the Spirit the word of wisdom; to another the word of knowledge by the same Spirit; To another faith by the same Spirit; to another the gifts of healing by the same Spirit; To another the working of miracles; to another prophecy; to another discerning of spirits; to another divers kinds of tongues; to another the interpretation of tongues: But all these worketh that one and the selfsame Spirit, dividing to every man severally as he will.

Since Jesus was casting out devils by the power of the Holy Spirit and here we see the gifts of the Spirit, are those that state speaking in tongues is blasphemy the ones actually committing blasphemy?

On the other hand, we know that God's Word is the truth.  Yet people interpret things differently in some points, such as whether or not tongues is no longer needed, whether or not we will be caught up before the tribulation, during it, or after it...things having nothing to do with the Gospel...the good new of Jesus. 

Titus 3:9

But avoid foolish questions, and genealogies, and contentions, and strivings about the law; for they are unprofitable and vain.

So could these be matters of interpretation on points that we shouldn't argue or could they be blasphemous?