Search Jim Cramer's "Mad Money" trading recommendations using our exclusive "Mad Money" Stock Screener.

NEW YORK (TheStreet) -- Investors were given a gift today, the gift of lower oil prices, Jim Cramer told his Mad Money viewers Wednesday. But once again, the promise of cheaper gasoline and heating oil sent the markets heading for the hills.

Make no mistake, cheaper crude is good for stocks. But for some reason the markets just haven't taken that message to heart.

Cramer's biggest worry about the markets are the transports, a sector that he featured Tuesday on Mad Money. But with crude prices falling, that means better gross margins and higher earnings for airlines like Southwest Airlines (LUV) - Get Report and Spirit Airlines (SAVE) - Get Report, Cramer's two favorites in the group.

Cheaper gasoline also directly correlates to restaurant and retail sales. Cramer gave the nod to Sonic (SONC) and Fiesta Restaurant Group (FRGI) - Get Report, as well as Macy's (M) - Get Report, up 18% for the year, and Home Depot (HD) - Get Report, up over 49% over the past 12 months that oil has been in decline.

But lower oil prices don't stop there. Even Apple (AAPL) - Get Report, a stock Cramer owns for his charitable trust, Action Alerts PLUS, will benefit, as consumers with more discretionary income will be flocking to the upcoming Apple Watch, the ultimate discretionary purchase.

Avoid the Activists

Never invest in a company just because an activist investor got involved, Cramer warned viewers.

Case in point: Children's Place (PLCE) - Get Report, the children's apparel retailer that has become a target of Macellum Advisors. Shares of Children's Place rallied 8.6% on the news Macellum and its partners are looking to shake up management, but that doesn't necessarily mean investors are in for a big windfall.

It's true that Children's Place has a long history of underperforming, with negative same-store sales and declining margins. It's also true the company's inventory levels are rising, management is leaving and its expansion plans have only resulted in the closing of underperforming locations.

That makes Children's Place a ripe target for activists but what about shareholders?

It turns out Macellum and its partners only have a 2% stake in Children's Place, which doesn't even put them in the company's top 10 list of largest shareholders. That means that while Macellum can make noise, there's no guarantee it can spur changes at the company. It's also not clear whether Macellum's strategy for turning Children's Place around is the right one.

Given all these issues, Cramer advised selling Children's Place into any strength because there are just too many unknowns. If things don't go Macellum's way, investors will only be left with a worst-of-breed retailer.

Agony and Ecstasy

Both the ecstasy and the agony of merger mania were on display today, with Mylan (MYL) - Get Report making a bid for Perrigo (PRGO) - Get Report, and Royal Dutch Shell( RDSA) paying up for BG Group.

The merger between Mylan and Perrigo was obvious, with the news sending Mylan shares up 14% and Perrigo up 18%. There are many synergies between the two companies and Perrigo's problems that kept its share price down are now well behind it.

But shares of Royal Dutch Shell, an Action Alerts PLUS holding, fell 3.4% as it was revealed that it's paying a 50% premium for BG, which is largely a natural gas provider. Cramer called the deal simply "embarrassing" as BG has been a terrible operator and there were a multitude of far better companies Shell could have purchased.

The Mylan deal was an instant wealth creator, Cramer concluded. The Shell deal was an instant wealth destroyer.

Off the Tape

In his "Off The Tape" segment, Cramer sat down with Ragy Thomas, founder and CEO of the privately held Sprinklr, a cloud-based social media management platform.

Thomas explained Sprinklr is an enterprise-level platform that allows companies to monitor and engage with their customers using over 20 different social platforms. He said brands have unique challenges in today's environment because discussions are happening all over the Internet and getting a unified picture of what's really going on is increasingly difficult.

Thomas said by using Sprinklr, companies can tap into the thoughts and opinions thousands of more customers than they ever could with focus groups or other channels.

Cramer said Sprinklr is at the epicenter of what's becoming an increasingly hot topic for enterprise software.

Lightning Round

In the Lightning Round, Cramer was bullish on Global Payments (GPN) - Get Report, VipShop (VIPS) - Get Report, First Solar (FSLR) - Get Report, Google (GOOGL) - Get Report, Pioneer Natural Resources (PXD) - Get Report and Receptos (RCPT) .

Cramer was bearish on 3D Systems (DDD) - Get Report, Freeport-McMoRan (FCX) - Get Report, Canadian Solar (CSIQ) - Get Report and Mobile Telesystems (MBT) - Get Report.

Am I Diversifed?

In the "Am I Diversified?" segment, Cramer spoke with callers and responded to tweets sent via Twitter to @JimCramer to see if investors' portfolios have what it takes for today's markets.

The first portfolio included Apple,EOG Resources (EOG) - Get Report, Kinder Morgan (KMI) - Get Report, Wendy's (WEN) - Get Report and Facebook (FB) - Get Report.

Cramer suggested selling EOG and adding a drug stock like Bristol-Myers Squibb (BMY) - Get Report to become better diversified.

The second portfolio's top holdings included Teva (TEVA) - Get Report, Perrigo, Pfizer (PFE) - Get Report, Carnival Cruises (CCL) - Get Report and Kroger (KR) - Get Report.

Cramer said this portfolio can't have three health care stocks. He advised adding United Technologies (UTX) - Get Report and Kinder Morgan to replace two of the drug stocks and be properly diversified.

The third portfolio had Apple, Ford (F) - Get Report, Gilead Sciences (GILD) - Get Report, Skyworks Solutions (SWKS) - Get Report and Schlumberger (SLB) - Get Report as its top five stocks.

Cramer said he wanted no changes made to this well-rounded portfolio.

To watch replays of Cramer's video segments, visit the Mad Money page on CNBC.

To sign up for Jim Cramer's free Booyah! newsletter with all of his latest articles and videos please click here.

At the time of publication, Cramer's Action Alerts PLUS had a position in AAPL, FB, GOOGL, KMI, RDS.A, SLB and UTX.