optimizing mySQL

[Surendra Singhi]

Hi,
  I am using mySQL 5.0 and I have 2 tables with few hundred millions of
records. 

To optimize things, I am using MyISAM tables, using the smallest possible data
type and have set indexes.

Now, the problem which I am facing is that mySql process is wasting lot of
time in disk access the CPU and memory utilization is very low. 
Most of the table access are simple queries, with very few write operations.

What can I do optimize things and make queries faster?

My CPU is 64bit Athlon 3000, with  950 MB of RAM running Ubuntu Edgy Eft.

I don't mind making mysql eat lot of CPU and RAM. Just want things to be much
faster, and loaded into memory instead of slow disk access.

The my.cnf file contains:

key_buffer              = 16M
max_allowed_packet      = 16M
thread_stack            = 128K

query_cache_limit       = 1048576
query_cache_size        = 16777216
query_cache_type        = 1

[isamchk]
key_buffer              = 16M

I am considering increasing these values, please advise on what should I set
them. Also, any other tips will be extremely helpful.

Thanks a lot.

-- 
Surendra Singhi
http://ssinghi.kreeti.com, http://www.kreeti.com