As chosen (and marketed) by Adventure Center.
Mont Blanc HighlightsKilimanjaro Climb – Rongai Route
Toubkal & the High Atlas
Everest Base Camp and Kala Patar
The Inca Trail
Walking the Great Wall
Ladakh: the Markha Valley
Ethiopia: The Simien Mountains
Torres del Paine Trek
Bhutan – The Snowman Trek
Not a bad list.
We’d replace the Inca Trail with one of the better treks in the Andes.
For details – Adventure Center
Personally, I’m looking at trekking Ladakh … independently. I can’t afford these tour prices. My budget is $40/day.
Ladakh: The Markha Valley
15 Days – from $2367A classic trek in ‘Little Tibet’, combining stunning mountain panoramas and barren hillsides with pretty villages and lush meadows
Isolated for many months of the year by snow, Ladakh remains one of the best places to experience the unique culture of the High Himalaya. Crossing the Ganda La we follow the Markha River, climbing through gorges, barley and mustard fields and picturesque Ladakhi villages. We hope to spot blue sheep and Ibex scrambling over the rocky slopes, with the stark peaks of the Stok, Matho and Zanskar ranges towering above.From the high-altitude yak pastures we have time to explore some of the surrounding peaks, and from the top of the highest pass, the Gongmaru La (5200m) we can enjoy incredible views of the Karakorum, the Himalaya and into Tibet. We end the trek with a spectacular walk down a gorge to Hemis, the largest and most famous of the Ladakhi monasteries.
besthike.com 
Can some one tell me about doing the Torres del Paine Trek without a guide?
Is September a good month to go? End of Sept?
September is a terrible month for Torres.
When we did it, the advice we got was not to start earlier than Dec. 1st.
Truly you want Jan – early March.
The weather is bad enough even at the best time of year.