I concur with previous poster - stop in Ipoh only if you're driving and need a break.

Although there are some nice sights to be had, particularly if you enjoy a flashback to a time where things moved a lot more slowly, Ipoh is decidely untouristy. The train station is old and worth a 5-minute look-see. I had some great dim-sum in Old Town (I'm told the "city" [that's being very generous] is split into 2 sections: old and new) with lots of character, noise, old men with bird cages etc and I'll never forget eating Ipoh Chicken Rice al fresco under electric poles teeming with crows at dusk. Summary: will probably appeal only to fans of "how it used to be in the old days" or Lat the cartoonist (his Town Boy graphic novel takes place in Ipoh)

If you're driving, the Chinese temple set in a limestone cave is called Sam Po Tong. You might also might want to make a stop here and there (if you're not on the PLUS highway) at roadside shops selling pomelo (a fruit very much like grapefruit), peanuts and chinese-style chicken crackers, all of which I was told were the signature produce of the region.

The 2 hotels that I've stayed in Penang were the Mutiara Beach Resort and the E&O Hotel (I stayed there pre-and-post the redo). The Mutiara (very nice though) is far away at the very end of Ferringhi Beach so out of the running here. E&O, close-in to town, was nice but pricey. I would take a look at tripadvisor. What might help you decide: Sunway, Berjaya, Cititel are well-known local hotel chains. Evergreen Laurel is a Taiwanese chain, also good. You'd probably want to stay in Georgetown which is the town/city area on Penang Island.