Yes you can put your UDMA66 drive and the UDMA33 drive both on the Highpoint controller and set the boot order in the bios to UDMA66 and it will boot from the drive on the Highpoint controller that has your operating system.
I would recommend not putting both drives on the same cable because the slower drive will probably slow the other one down. You may also put one drive on one of the regular IDE ports, UDMA33, and the the other on the Highpoint controller, UDMA66. As long as you specify the proper boot seqence in the bios.
I would also have to warn that I have had nothing but trouble with the highpoint controller when the system fsb is set to 133. I have used a maxtor 7200 rpm UDMA66 H/D, IBM 7200 rpm UDMA H/D, Fujitsu 7200 rpm UDMA66 H/D and Seagate 7200 rpm UDMA66 H/D and the Seagate is the only one that will boot and run with a 133 fsb.