I grew up there, so I do know some about the area.
Obviously someone said Daisy Dooks
- if trashy strip clubs are your thing.
Two riverboat casinos and one land-based casino - Isle of Capri in Bettendorf are Rhythm City in Davenport the two riverboats, and Jumer's is the land-based in the outskirts of Rock Island (I-280 and IL-92). By far Jumer's is the nicest.
If you're the club-hopping type or the general entertainment type there's always something in the District of Rock Island. I couldn't tell you what bars are down there as I haven't been in the bar scene for 5+ years, but there's always something down there.
I'd look into Comedy Sportz in the District. That is almost always good for a laugh.
If you're into hockey and in town tomorrow evening the Quad City Mallards play their season finale at the iWireless Center.
For restaurants the Quad Cities tends to be Chain City, so the easy option is find your favorite chain and you'll likely find it there. However, if you want to avoid that, there's multiple choices in the Village of East Davenport. However, two of my favorites, Belgian Village and The Bier Stube, are both in Downtown Moline (Bier Stube also has a location in the East Village). One thing you MUST do is Whitey's Ice Cream. Best ice cream in the Midwest (it's the one thing I really miss from home).
As far as hotels, it really depends on your tastes and what you're willing to spend. Personally, I'm a fan of Hampton Inns. Always clean and reasonably priced, and always a free breakfast in the morning. Plus I like racking up HiltonHonors points.
This might be a little bit more helpful if you were a little bit more specific about your interests, if you were looking for "single-guy" entertainment or family entertainment, what you were willing to spend, etc. This is just a shot in the dark.