Digidave, it sounds like your best bet would be to wait until your area is upgraded to VDSL which will allow you to watch or record at least 2 HD and 1 SD channels at once.
If you are only eligible for the 15 Mbps profile, then you can only get 1 HD and 2 SD streams at a time. You'll see a lot of discussion of that in this forum. You may wish to call Telus back and confirm that you will only get the 15 Mbps profile. The best way to double-check that is to ask them how many HD and SD streams you can get.