Connecting two relative clauses in one sentence

Solution 1:

I would simplify it by omitting some of the relative pronouns.

Figures 1 and 2 show the percentage of people age 25 and over who purchased concert, cinema and theater tickets online during the first three months of 2006 in Australia, the UK and Malaysia.

I believe this is clear, concise and grammatically correct.

(is it really necessary to say 25-44 and over, since that includes everyone over 44 as well?)

Solution 2:

"Figure 1 and figure 2 show the percentage of people whose age is between 25-44 and over, and who purchased concert, cinema and theater tickets online over the first three months of 2006, in three countries, which are Australia, the UK, and Malaysia."

I've omitted the comma after "people", since the sense of the following relative clause is restrictive. I kept the comma after "over" because there is an intonation break here in the pronunciation. I added a comma after "2006", also because of the pronunciation, and to make clearer that the following prepositional phrase goes with the preceding verb phrase that starts with "purchased". The last relative clause is non-restrictive, so it keeps the comma you put after "countries". I added "and" before "Malaysia" (but the preceding comma perhaps should be omitted).