* Disney rises as Star Wars breaks box-office records
* Microsoft biggest boost to S&P 500, Nasdaq
* Apple up 1 percent
* Indexes up: Dow 0.68 pct, S&P 0.69 pct, Nasdaq 0.71 pct (Updates to open)
By Abhiram Nandakumar
Dec 21 (Reuters) - Wall Street started the Christmas holiday week on a positive note, led by tech and financials, but energy stocks lagged as Brent crude hit an 11-year low.
Trading volumes are expected to be relatively light this week, with U.S. stock markets operating a shortened session on Thursday and closing on Friday for Christmas.
U.S. stock indexes are coming off two days of heavy losses as weak crude prices dampened the effect of the first Federal Reserve interest rate hike in nearly a decade.
Oil prices have been sliding under continued pressure from global oversupply and tepid demand.
"There looks to be like a little relief bounce this morning as we move into the last two weeks of the year," said Andre Bakhos, managing director at Janlyn Capital LLC in Bernardsville, New Jersey.
"It's a fickle market. All you have to do is look at what we've done for the year and whatever you're going to see today, there's lower confidence in the direction of any move," he said.
Although the S&P 500 touched record highs in 2015, the index is down 2.6 percent for the year, buffeted by slowing growth in China, slump in commodities and uncertainty over U.S. interest rates. The Dow Jones industrial average is down 3.9 percent.
The Nasdaq Composite, which briefly breached its dotcom highs this year, is the only one of the three major indexes in the black, having risen 3.9 percent so far in 2015.
At 9:39 a.m. ET (1439 GMT), the Dow Jones industrial average was up 117.29 points, or 0.68 percent, at 17,245.84, the S&P 500 was up 13.75 points, or 0.69 percent, at 2,019.3 and the Nasdaq Composite index was up 34.88 points, or 0.71 percent, at 4,957.96.
All 10 major S&P sectors were higher, led by the financial sector's 1.2 percent rise.
Berkshire shares were up 1.5 percent and provided the biggest boost to the financials sector, while Microsoft was the biggest influence to the S&P and the Dow.
Microsoft was up 1.6 percent at $54.98 after a Barron's report on Sunday that the Windows operating system maker's shares could rise 30 percent over the next 18 months.
Apple was up 1.1 percent at $107.19. The iPhone maker signed a patent-licensing deal with Swedish mobile telecom gear maker Ericsson, ending a year-long dispute.
Disney shares were up 0.7 percent at $108.62 as "Star Wars: The Force Awakens" shattered box office records with an estimated $517 million in worldwide ticket sales through Sunday.
Advancing issues outnumbered decliners on the NYSE by 2,019 to 690. On the Nasdaq, 1,592 issues rose and 772 fell.
The S&P 500 index showed one new 52-week high and 6 new lows, while the Nasdaq recorded 16 new highs and 28 new lows. (Reporting by Abhiram Nandakumar in Bengaluru; Editing by Saumyadeb Chakrabarty)