A Raleigh is not going to be much better, since it also uses a different size 26" tire, and is all loaded with non-standard parts, which can't be easily replaced. (Raleighs also have steel wheels, they were trying to convince the world that STEEL WAS BETTER! (Raleigh: The ALL STEEL Bicycle! So, why did they use that little plastic roller fulcrum in the shift mechanismthat always crumbles after a few years?)

I'd go ahead with the Sears bike, and start collecting money for Wheels and tires as a first upgrade. I'd look up a YUBA Mundo Dealer, and buy a set of wheels for the 2010 Yuba Mundo, but thats because I weigh a FAIR amount, and YUBA wheels will last basically forever. Or see if craigslist will steer you to a Mountain bike Tandem (yes, there are MTB tandems, Virgina!) The Raleigh wheels can be rebuilt, using the original hubs and donor rims, and you do get more spokes than cheap sears bikes. The 2009 Yuba replacement wheels are about $100, keep that in mind, and, they now can be used with optional disc brakes at extra cost, in which the rim is not part of the brakes. If you want to upgrade the Sears wheels to disks, you will probably need to rebuild the wheels anyway. as well as buy the brakes. No help there.

Wal-Mart can be a good cheap source of tires but make sure you know what to buy, since they will not help you buy appropriate tires, and there are about 6 different sizes of 26" bike tires still made for 70s bikes. I bough my Raleigh some new shoes at the local Wal-Mart, cheap - under $8 /wheel for tires and tubes.

Just be sure you get both a front wheel and rear wheel, whatever you do, and tires to fit. TUBES are also a problem in that are two major types of tubes: Standard/Schraeder and the smaller Presta openings (yes there are others, antique "English"/Dunlop, you'll see those about as often as Whitworth threaded bolts.)