Upgrading the Roadie - Components?

Here's the dealio...in 2001, I got a Klein Quantum that I love...I bought it for the frame, and it came with a full 105 group, 9 speed. I want to use this as my everyday rider, but the group is starting to get 'soft'. Shifts aren't crisp. Shift levers have a little play. Now, to be fair, I've never done much maintenance to the group...never tightened the cables, greased or replaced bearings...about the only maintenance I've done is to swap the cassette, and cleaning the drivetrain, which I've done fairly often.

So at this point, I'm pretty convinced I need at least 4 things: New cables, New chainring, Overhaul the BB, and a new chain, plus a good cleaning, plus tighten up the brake cables. Now come the options:

Option 1: Buy only what I listed out above, 105 or ultegra, and get the bike overhauled for probably $350
   - Pros: Relatively inexpensive
   - Cons: Still have 9-speed, still have (predominantly) 105 components, some of which are ~9 years old

Option 2: Buy a new Ultegra SL group on eBay or elsewhere for $850
   - Pros: Get to 10-speed, get to ultegra,
   - Cons: Relatively expensive, replacing some components (like the FD hanger, cassette) that I don't need to

Option 3: Buy a Windsor Falkirk for $895 (comes with Ultegra), swap the gruppo, end up with two fully working bikes.
   - Pros: Get to 10 speed, get to ultegra, get a bonus frame, fork, and Shimano R500 wheels (bonus!  the Rolfs
     that came on the bike are out of round).  
   - Cons: Relatively expensive.

So as I think about these options, I've pretty much ruled out option 2. But there are a couple things that would help me decide between options 1 and 3:
   - Is the difference between 2001 105 and 2009 Ultegra SL that much?  Is it signficant?
   - How are the Shimano R500 wheels - are they dogs, or are they all-around decent wheels?
   - Any other considerations for upgrading the 9-speed?

The goal here is to build a good, everyday performer, not necessarily to break any weight weenie records or deck the halls with carbon. Any feedback would be appreciated, including things I haven't thought of. Thanks in advance.