Kass, you may want to start at your hotel and map a walk up to Central Park.

You can start at ground zero, walk East across Vesey St. to Park Row (see the Brooklyn Bridge) where you then head North, up through China Town (see the Manhattan Bridge) and Little Italy (to do that continue on Centre St. from Park Row to get to Canal); - Turn right on Canal St. You can walk down to the East End of it to see the Manhattan Bridge if you want, but don't head North from there - you don't want to see "alphabet city" (unless you want to score some drugs and maybe get mugged). So instead, head back to Mott Street or Mulberry Street, and head North up through Little Italy. They both run out at Bleeker St - jog a little West to Broadway, and head up to Fourth. You can head a little East (on Bleeker or 4th - or zig zag between them) to see East Village, then head West to see Greenwich Village - find some place to grab a bite for lunch.
Then keep heading North on 6th or 7th Ave or Broadway (which goes diagonally) (don't really want to be too far west of 7th there - some not so nice neighborhoods) and walk up through Chelsea, the garment district (not exciting), up to Times Square (which is basically where Broadway and 7th intersect). Then head over to 6th Ave on 48th St. to see Rockefeller Center (the rink and such are between 48th and 49th St. on 5th Ave) - then keep going up 5th Ave. (or Madison) to see Central Park (which is up at 59th St.). St. Patrick's Cathedral is worth a visit - it's on Madison (one block east of 5th) between 50th & 51st St. Don't know if DH is any kind of "techie" or not, but Sony is on Madison between 55th and 56th. And FYI, Central Park is at 59th St, and spans 5th Avenue to Columbus Circle (the bottom end of it).
But the "ritzy" fun window shopping is on 5th and/or Madison (Avenues next to each other), between 50th and 59th basically.
Note: Distance between "streets" is like a normal block - distance between Avenues is long - like the equivalent of 2 or 3 "street" blocks.
You may be exhausted by then, so while I hate that the carriage rides exist, you may want to consider a carriage ride through Central Park - and take a cab back to your hotel so you can pass out.

Central Park in the fall/winter with nothing blooming and the leaves off the trees isn't as exciting as in the summer or during fall colors - so if you want to sight see in central park, get a map and go find things like the Promenade or the statue of Alice in Wonderland - that kind of stuff.

Just remember - Avenues go North and South. There are some avenues with "names" and not numbers - Broadway, Madison, Park, and Lexington (going from West to East - well in Midtown, because Broadway slices diagnoally from West to East and heads all the way down to the bottom tip of the island at the Ferry to Staten Island/Battery Park), and the Avenue numbers get smaller as you go from West to East (from 11th next to the West Side Highway) to 1st Ave (near to the FDR Drive, though for a good part up North York Ave is inbetween the FDR and 1st) - which just kind of abruptly ends at Houston St. Because the island gets skinny as you go south, 11th Avenue actually starts at 23rd St.
And the "streets" (as opposed to the avenues) get larger (higher numbers) as you go North.
...but below 4th St (East Village, West Village, Greenwich Village, Soho...and neighborhoods south of there like little Italy, China Town and the Financial district), there are a million little crazy streets, and the number system doesn't really work LOL.
Canal Street (towards the East side) divides China Town and Little Italy.
